Diastereoselective Synthesis of Spiro[pyrazolone-4,3′-tetrahydrothiophenes] via a Sulfa-Michael/Aldol Domino Reaction

Synthesis : journal of synthetic organic chemistry 48(23), 4091-4098(2016). doi:10.1055/s-0035-1562473

Asymmetric Synthesis of Five-Membered Spiropyrazolones via N-Heterocyclic Carbene (NHC)-Catalyzed [3+2] Annulations

A new synthetic strategy for the asymmetric synthesis of five-membered spiropyrazolones via N-heterocyclic carbene-catalyzed [3+2] annulations employing enals and unsaturated pyrazolones as substrates has been developed. The new protocol allows the flexible variation of all four substituents of the pharmaceutically important spiropyrazolones in moderate to very good yields and in most cases with excellent diastereoselectivities and good to excellent enantioselectivities.

Thiourea-Catalyzed Domino Michael–Mannich [3+2] Cycloadditions: A Strategy for the Asymmetric Synthesis of 3,3′-Pyrrolidinyl-dispirooxindoles

The asymmetric synthesis of trifluoromethylated 3,3′-pyrrolidinyl-dispirooxindole derivatives with four contiguous stereogenic centers, including two vicinal spiro-stereocenters, is described. Employing a bifunctional thiourea catalyst, a domino Michael–Mannich [3+2] cycloaddition occurs readily between isatin ketimines and isatin-derived enoates with good yields and very high stereoselectivities, providing a direct entry to the title compounds of potential medical value.

Asymmetric synthesis of cyclopentanes bearing four contiguous stereocenters via an NHC-catalyzed Michael/Michael/esterification domino reaction.

An NHC-catalyzed Michael/Michael/esterification domino reaction via homoenolate/enolate intermediates for the asymmetric synthesis of tetrasubstituted cyclopentanes is described.

Control of N-Heterocyclic Carbene Catalyzed Reactions of Enals: Asymmetric Synthesis of Oxindole-γ-Amino Acid Derivatives.

A strategy to control the switch between a non‐cycloaddition reaction and a cycloaddition reaction of enals, using N‐heterocyclic carbene (NHC) catalyisis, has been developed. The new scalable protocol leads to γ‐amino‐acid esters bearing a tetrasubstituted stereocenter in good yields and high stereoselectivities by homo‐Mannich reactions of enals and isatin‐derived ketimines. By simply changing the N‐ketimine substituent to an ortho‐hydroxy phenyl group, the corresponding spirocyclic oxindolo‐γ‐lactams are obtained. peerReviewed

ChemInform Abstract: Asymmetric Synthesis of Cyclopentanes Bearing Four Contiguous Stereocenters via an NHC-Catalyzed Michael/Michael/Esterification Domino Reaction.

An NHC-catalyzed Michael/Michael/esterification domino reaction via homoenolate/enolate intermediates for the asymmetric synthesis of tetrasubstituted cyclopentanes bearing four contiguous stereocenters is described. A variety of α,β-unsaturated aldehydes and 2-nitroallylic acetates react well with good domino yields and high stereoselectivities.

Enantioselective Total Syntheses of (+)-Hippolachnin A, (+)-Gracilioether A, (-)-Gracilioether E, and (-)-Gracilioether F.

The Plakortin polyketides represent a structurally and biologically fascinating class of marine natural products. Herein, we report a unified strategy that enables the divergent syntheses of various Plakortin polyketides with high step-economy and overall efficiency. As proof-of-concept cases, the enantioselective total syntheses of (+)-hippolachnin A, (+)-gracilioether A, (-)-gracilioether E, and (-)-gracilioether F have been accomplished based on a series of bio-inspired, rationally designed, or serendipitously discovered transformations, which include (1) an organocatalytic asymmetric 1,4-conjugate addition to assemble the common chiral γ-butenolide intermediate enroute to all of the afo…

Asymmetric Synthesis of Spiro β-Lactamsviaa Squaramide- Catalyzed Sulfa-Michael Addition/Desymmetrization Protocol

An efficient asymmetric synthesis of spirocyclohexenone β-lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide-catalyzed sulfa-Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5-cyclohexadienones.

N-Heterocyclic Carbene Catalyzed [3+2] Cycloaddition of Enals with Masked Cinnamates for the Asymmetric One-Pot Synthesis of Adipic Acid Derivatives.

A novel short entry to 3,4-disubstituted adipic acids has been developed by employing an asymmetric NHC-catalyzed [3+2] cycloaddition of enals with masked cinnammates in moderate to good yields and high stereoselectivities. The synthetic utility of the protocol was demonstrated by the basic conversion of the masked cyclopentanone intermediates to 3S,4S-disubstituted adipic acid precursors of pharmaceutically important gababutins.

N-Heterocyclic Carbene Catalyzed Quadruple Domino Reactions through α,β-Unsaturated Acyl Azolium Intermediates : Asymmetric Synthesis of Cyclopenta[c]chromenones

An N‐heterocyclic carbene catalyzed domino sequence via α,β‐unsaturated acyl azolium intermediates has been developed. This strategy provides a convenient enantioselective route to functionalized tricyclic coumarin derivatives and cyclopentanes. DFT studies and control experiments were performed to gain better insight into the reaction mechanism. peerReviewed

Asymmetric synthesis of functionalized tetrahydrofluorenones via an NHC-catalyzed homoenolate Michael addition

The first example of an N-heterocyclic carbene-catalyzed asymmetric desymmetrization of enal-tethered cyclohexadienones via an intramolecular homoenolate Michael addition/esterification reaction is described. This new protocol offers a direct entry to various functionalized tetrahydrofluorenones with three contiguous stereocenters in high yields, good diastereoselectivities and excellent enantioselectivities.

Asymmetric synthesis of 3,3′-pyrrolidinyl-dispirooxindoles via a one-pot organocatalytic Mannich/deprotection/aza-Michael sequence

Chemical communications 52, 2249-2252 (2016). doi:10.1039/C5CC10057G

Organocatalytic Asymmetric Synthesis of 2,3′-Connected Bis-Indolinones by Mannich Reactions of N-Acetylindolin-3-ones with Isatin N-Boc Ketimines

A highly diastereo- and enantioselective Mannich reaction of N-acetylindolin-3-ones with isatin N-Boc ketimines to form 2,3′-connected bis-indolinones is developed employing a low loading of a readily available bifunctional thiourea catalyst. The asymmetric synthesis connects two indolinones via a vic-diamine unit and generates two neighboring stereocenters.

Asymmetric Synthesis of Spiro Tetrahydrothiophene-indan-1,3-diones via a Squaramide-Catalyzed Sulfa-Michael/Aldol Domino Reaction

Synthesis 48(08), 1131-1138(2016). doi:10.1055/s-0035-1560412

Highly Enantioselective Kinetic Resolution of Michael Adducts through N-Heterocyclic Carbene Catalysis: An Efficient Asymmetric Route to Cyclohexenes

Ahighly efficient strategy for the kinetic resolu-tion of Michael adductswas realized using achiral N-het-erocyclic carbene catalyst.The kinetic resolution providesanew convenientroute to single diastereomers of cyclo-hexenes and Michael adducts in good yields with highenantiomeric excesses (up to 99 % ee with aselectivityfactor of up to 458). This “two flies with one swat” con-cept allows the synthesis of these two synthetically valua-ble compound classes at the same time by asingle trans-formation. peerReviewed

N-Heterocyclic Carbene-Catalyzed Activation of α-Chloroaldehydes: Asymmetric Synthesis of 5-Cyano-Substituted Dihydropyranones

An N-heterocyclic carbene (NHC)-catalyzed asymmetric [4+2] annulation of (E)-2-benzoyl-3-phenylacrylonitriles with α-chloroaldehydes has been developed. The protocol leads to 5-cyano-substituted dihydropyranones in good to excellent yields with excellent diastereo- and enantioselectivities (up to 93% yield, >20:1 d.r. and 99% ee).

Combining organocatalysis and lanthanide catalysis: a sequential one-pot quadruple reaction sequence/hetero-Diels-Alder asymmetric synthesis of functionalized tricycles

A stereoselective one-pot synthesis of functionalized complex tricyclic polyethers has been achieved using the combination of secondary amine and lanthanide catalysis. This one-pot quadruple reaction/Hetero-Diels–Alder sequence gave good yields (per step) as well as excellent diastereo- and enantioselectivities. Furthermore, the particular combination of lanthanide complexes with organocatalysis is one of the first examples described for sequential catalysis.

Cover Feature: Highly Enantioselective Kinetic Resolution of Michael Adducts through N-Heterocyclic Carbene Catalysis: An Efficient Asymmetric Route to Cyclohexenes (Chem. Eur. J. 39/2018)

Asymmetric Synthesis of Functionalized Tricyclic Chromanes via an Organocatalytic Triple Domino Reaction

A highly stereoselective triple domino reaction for the synthesis of functionalized tricyclic chromane scaffolds has been developed. A secondary amine-catalyzed domino Michael/Michael/aldol condensation reaction between aliphatic aldehydes, nitro-chromenes, and α,β-unsaturated aldehydes leads to the formation of synthetically important tricyclic chromanes bearing four contiguous stereogenic centers including a tetrasubstituted carbon in good yields (20–66%) and excellent stereoselectivities (>20:1 dr and >99% ee).

Asymmetric Synthesis of Spirocyclic β-Lactams through Copper-Catalyzed Kinugasa/Michael Domino Reactions

The first copper-catalyzed highly chemo-, regio-, diastereo-, and enantioselective Kinugasa/Michael domino reaction for the desymmetrization of prochiral cyclohexadienones is described. In the presence of a chiral copper catalyst, alkyne-tethered cyclohexadienones couple with nitrones to generate the chiral spirocyclic lactams with excellent stereoselectivity (up to 97 % ee, >20:1 dr). The new method provides direct access to versatile highly functionalized spirocyclic β-lactams possessing four contiguous stereocenters, including one quaternary and one tetra-substituted stereocenter.

Organocatalytic Enantioselective Vinylogous Henry Reaction of 3,5-Dimethyl-4-nitroisoxazole with Trifluoromethyl Ketones

The enantioselective vinylogous Henry reaction of 3,5-dimethyl-4-nitroisoxazole with trifluoromethyl ketones employing a bifunctional squaramide organocatalyst has been developed. A series of isoxazole bearing trifluoromethyl-substituted tertiary alcohols, 2-substituted (R)-1,1,1-trifluoro-3-(3-methyl-4-nitroisoxazol-5-yl)propan-2-ols, were obtained under these mild reaction conditions in good yields and moderate to good enantioselectivities

Asymmetric Synthesis of Spirocyclic β‐Lactams via Copper‐Catalyzed Kinugasa/Michael Domino Reactions

The first copper‐catalyzed highly chemo‐, regio‐, diastereo‐, and enantioselective Kinugasa/Michael domino reaction for the desymmetrization of prochiral cyclohexadienones is described. In the presence of a chiral copper catalyst, alkyne‐tethered cyclohexadienones couple with nitrones to generate the chiral spirocyclic lactams with excellent stereoselectivity (up to 97 % ee, >20:1 dr). The new method provides direct access to versatile highly functionalized spirocyclic β‐lactams possessing four contiguous stereocenters, including one quaternary and one tetra‐substituted stereocenter. peerReviewed

N‐Heterocyclic Carbene Catalyzed Asymmetric Synthesis of Pentacyclic Spirooxindoles via [3+3] Annulations of Isatin‐Derived Enals and Cyclic N‐Sulfonyl Ketimines

Asymmetric Organocatalytic Synthesis of 4-Aminoisochromanones via a Direct One-Pot Intramolecular Mannich Reaction

Synthesis 48(24), 4451 - 4458(2016). doi:10.1055/s-0035-1562522

N-Heterocyclic Carbene Catalyzed Asymmetric Synthesis of Pentacyclic Spirooxindoles via [3+3] Annulations of Isatin-Derived Enals and Cyclic N-Sulfonyl Ketimines

A convenient enantioselective route to new types of pentacyclic spirooxindoles via [3+3] annulation reactions of isatin-derived enals and cyclic N-sulfonyl ketimines, using N-heterocyclic carbene (NHC) catalysis has been developed. The new protocol leads to pentacyclic spirooxindoles bearing a quaternary spirostereocenter in good yields and good to high enantiomeric ratios. peerReviewed

Asymmetric Synthesis of Spirobenzazepinones with Atroposelectivity and Spiro-1,2-Diazepinones by NHC-Catalyzed [3+4] Annulation Reactions

A strategy for the NHC-catalyzed asymmetric synthesis of spirobenzazepinones, spiro-1,2-diazepinones, and spiro-1,2-oxazepinones has been developed via [3+4]-cycloaddition reactions of isatin-derived enals (3C component) with in-situ-generated aza-o-quinone methides, azoalkenes, and nitrosoalkenes (4atom components). The [3+4] annulation strategy leads to the seven-membered target spiro heterocycles bearing an oxindole moiety in high yields and excellent enantioselectivities with a wide variety of substrates. Notably, the benzazepinone synthesis is atroposelective and an all-carbon spiro stereocenter is generated.

Asymmetric Synthesis of Spiro-oxindole-ε-lactones through N-Heterocyclic Carbene Catalysis

An unprecedented N-heterocyclic carbene-catalyzed annulation of isatin-derived enals and o-hydroxyphenyl-substituted p-quinone methides as bifunctional reagents has been discovered. The new protocol involves a 1,6-addition of the homoenolate equivalent intermediates to the hydroxy donor-1,6-Michael acceptors and leads to spirocyclic oxindole-ε-lactones in high yields and very good stereoselectivities.

N‐Heterocyclic Carbene Catalyzed Quadruple Domino Reactions: Asymmetric Synthesis of Cyclopenta[ c ]chromenones

An N-heterocyclic carbene catalyzed domino sequence via α,β-unsaturated acyl azolium intermediates has been developed. This strategy provides a convenient enantioselective route to functionalized tricyclic coumarin derivatives and cyclopentanes. DFT studies and control experiments were performed to gain better insight into the reaction mechanism.

Enantioselective synthesis of pyrazolone α-aminonitrile derivatives via an organocatalytic Strecker reaction

A new organocatalytic enantioselective Strecker reaction of pyrazolone-derived ketimine electrophiles has been developed. Using pseudo-enantiomeric squaramide catalysts the nucleophilic 1,2-addition of trimethylsilyl cyanide to the ketimines efficiently provides a direct entry to both enantiomers of pyrazolone α- aminonitrile derivatives at will in good yields and high enantioselectivities for a wide variety of substrates. peerReviewed

Enantioselective Total Syntheses of (+)-Hippolachnin A, (+)-Gracilioether A, (-)-Gracilioether E and (-)-Gracilioether F

The Plakortin polyketides represent a structurally and biologically fascinating class of marine natural products. Herein, we report a unified strategy that enables the divergent syntheses of various Plakortin polyketides with high step-economy and overall efficiency. As proof-of-concept cases, the enantioselective total syntheses of (+)-hippolachnin A, (+)-gracilioether A, (−)-gracilioether E, and (−)-gracilioether F have been accomplished based on a series of bio-inspired, rationally designed, or serendipitously discovered transformations, which include (1) an organocatalytic asymmetric 1,4-conjugate addition to assemble the common chiral γ-butenolide intermediate enroute to all of the afo…

Synthesis of trans-disubstituted-2,3-dihydrobenzofurans by a formal [4 + 1] annulation between para-quinone methides and sulfonium salts

An efficient protocol for the synthesis of trans-disubstituted-2,3-dihydrobenzofurans through [4 + 1] annulation of para-quinone methides with sulfonium salts has been developed. Under very mild conditions this unprecedented reaction occurs in good to excellent yields (up to 99%), offering a straightforward access to a variety of 2,3-dihydrobenzofurans.

Organocatalytic Asymmetric Synthesis of Trifluoromethylated Tetrahydrocarbazoles by a Vinylogous Michael/Aldol Formal [4+2] Annulation

Squaramide-Catalyzed Asymmetric aza-Friedel-Crafts/N,O-Acetalization Domino Reactions Between 2-Naphthols and Pyrazolinone Ketimines

N-Boc ketimines derived from pyrazolin-5-ones were explored to develop an unprecedented domino aza-Friedel-Crafts/N,O-acetalization reaction with 2-naphthols. The novel method requires a catalyst loading of only 0.5 mol % of a bifunctional squaramide catalyst, is scalable to gram amounts, and provides a new series of furanonaphthopyrazolidinone derivatives bearing two vicinal tetra-substituted stereogenic centers in excellent yields (95-98 %) and stereoselectivity (>99:1 d.r. and 97-98 % ee). A different reactivity was observed in the case of 1-naphthols and other electron-rich phenols, which led to the aza-Friedel-Crafts adducts in 70-98 % yield and 47-98 % ee.

N-Heterocyclic Carbene Catalyzed Asymmetric Synthesis of Dihydropyranothiazoles­ via Azolium Enolate Intermediates

A highly diastereo- and enantiostereoselective synthesis of bicyclic dihydropyranothiazoles combining a thiazole and δ-lactone skeleton via NHC-catalyzed [4+2] annulation of 5-alkenylthiazolones and α-chloroaldehydes has been developed. The heterocyclic products are formed via azolium enolate intermediates in good yields with high diastereo- and enantistereoselectivities.

Asymmetric Synthesis of Tetrahydrobenzofurans and Annulated Dihydropyrans via Cooperative One-Pot Organo- and Silver-Catalysis

Synthesis : journal of synthetic organic chemistry 48(19), 3207-3216(2016). doi:10.1055/s-0035-1561468

Organocatalytic Domino Oxa-Michael/1,6-Addition Reactions: Asymmetric Synthesis of Chromans Bearing Oxindole Scaffolds.

An asymmetric organocatalytic domino oxa-Michael/1,6-addition reaction of ortho-hydroxyphenyl-substituted para-quinone methides and isatin-derived enoates has been developed. In the presence of 5 mol % of a bifunctional thiourea organocatalyst, this scalable domino reaction affords 4-phenyl-substituted chromans bearing spiro-connected oxindole scaffolds and three adjacent stereogenic centers in good to excellent yields (up to 98 %) and with very high stereoselectivities (up to >20:1 d.r., >99 % ee).

Organocatalytic Oxa-Michael/Michael/Michael/Aldol Condensation Quadruple Domino Sequence : Asymmetric Synthesis of Tricyclic Chromanes

An efficient and highly stereoselective one-pot, four-component synthesis of functionalized tricyclic chromanes has been achieved through an organocatalyzed quadruple domino reaction. The reaction sequence involves an oxa-Michael/Michael/Michael/aldol condensation between alcohols, 2 equiv of acrolein, and nitrochromenes to generate the pharmaceutically important tricyclic chromanes bearing three contiguous stereogenic centers including a chiral tetrasubstituted carbon center in good domino yields (30–70%) and excellent diastereo- and enantioselectivities (>20:1 dr and >99% ee). peerReviewed

Enantioselective synthesis of 4H-pyranonaphthoquinones via sequential squaramide and silver catalysis

Chemical communications 52(8), 1669-1672(2016). doi:10.1039/C5CC09592A

Switchable Access to Different Spirocyclopentane Oxindoles by N-Heterocyclic Carbene Catalyzed Reactions of Isatin-Derived Enals and N-Sulfonyl Ketimines

A novel NHC-catalyzed annulation protocol for the asymmetric synthesis of biologically important β-lactam fused spirocyclopentane oxindoles with four contiguous stereocenters, including two quaternary carbon centers, was developed. Alternatively, spirocyclopentane oxindoles containing an enaminone moiety can be achieved using the same starting materials, isatin-derived enals, and N-sulfonyl ketimines, in the presence of a slightly different NHC catalytic system. This switchable annulation strategy enables the selective assembly of both heterocyclic scaffolds with good yields and excellent enantioselectivities for a broad range of substrates.

Asymmetric, Three-Component, One-Pot Synthesis of Spiropyrazolones and 2,5-Chromenediones from Aldol Condensation/NHC-Catalyzed Annulation Reactions

A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolones, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC)-catalyzed [3+2] annulation. The desired spirocyclopentane pyrazolones are obtained in moderate to good yields and good to excellent stereoselectivities. Alternatively, starting from cyclic 1,3-diketones, 2,5-chromenediones are available through [2+4] annulation.

N‐Heterocyclic Carbene Catalyzed [4+2] Annulation of Enals via a Double Vinylogous Michael Addition: Asymmetric Synthesis of 3,5‐Diaryl Cyclohexenones

A strategy for the N-heterocyclic carbene (NHC) catalyzed asymmetric synthesis of 3,5-diaryl substituted cyclohexenones has been developed via oxidative [4+2] annulation of enals and alkenylisoxazoles. It is the first example of using NHC organocatalysis in a double vinylogous Michael type reaction, a challenging but highly desirable topic. This unprecedented protocol affords good yields as well as high to excellent diastereo- and enantioselectivities.

Palladium Catalyzed [3+2] Cycloaddition of Vinyl Aziridine and Indane-1,3-diones: Diastereo- and Enantioselective Access to Spiro-Pyrrolidines

A mild and efficient palladium-catalyzed [3+2] cycloaddition of vinylaziridine and indane-1,3-diones has been realized. The resulting spiro-pyrrolidines were provided in excellent yields and, with the introduction of the leucine-derived phosphine ligand, moderate to good enantio­- and diastereoselectivities.

Asymmetric Synthesis of Amino-Bis-Pyrazolone Derivatives via an Organocatalytic Mannich Reaction.

A new series of N-Boc ketimines derived from pyrazolin-5-ones have been used as electrophiles in asymmetric Mannich reactions with pyrazolones. The amino-bis-pyrazolone products are obtained in excellent yields and stereoselectivities by employing a very low loading of 1 mol % of a bifunctional squaramide organocatalyst. Depending on the substitution at position 4 of the pyrazolones, the new protocol allows for the generation of one or two tetrasubstituted stereocenters, including a one-pot version combing the Mannich reaction with a base-mediated halogenation. peerReviewed

CCDC 1831622: Experimental Crystal Structure Determination

Related Article: Tao Shu, Long Zhao, Sun Li, Xiang-Yu Chen, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Angew.Chem.,Int.Ed.|57|10985|doi:10.1002/anie.201806931

CCDC 1818911: Experimental Crystal Structure Determination

Related Article: Xiang‐Yu Chen, Sun Li, Qiang Liu, Mukesh Kumar , Anssi Peuronen, Kari Rissanen, Dieter Enders|2018|Chem.-Eur.J.|24|9735|doi:10.1002/chem.201802420

CCDC 1534938: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Marcus Blümel, Rakesh Puttreddy, Anssi Peuronen, Kari Rissanen, Dieter Enders|2017|Angew.Chem.,Int.Ed.|56|8516|doi:10.1002/anie.201704210

CCDC 1516205: Experimental Crystal Structure Determination

Related Article: Sun Lia, Lei Wang, Pankaj Chauhan, Anssi Peuronen, Kari Rissanen, Dieter Enders|2017|Synthesis|49|1808|doi:10.1055/s-0036-1588381

CCDC 1549337: Experimental Crystal Structure Determination

Related Article: Ying Zhi, Kun Zhao, Carolina von Essen, Kari Rissanen, Dieter Enders|2017|Synlett|28|2876|doi:10.1055/s-0036-1589070

CCDC 1453056: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Marcus Blümel, Arne R. Philipps, Ai Wang, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2016|Angew.Chem.,Int.Ed.|55|11110|doi:10.1002/anie.201604819

CCDC 1542055: Experimental Crystal Structure Determination

Related Article: Suruchi Mahajan, Pankaj Chauhan, Uğur Kaya, Kristina Deckers, Kari Rissanen, Dieter Enders|2017|Chem.Commun.|53|6633|doi:10.1039/C7CC02874A

CCDC 1474771: Experimental Crystal Structure Determination

Related Article: Uğur Kaya, Pankaj Chauhan, Kristina Deckers, Rakesh Puttreddy, Kari Rissanen, Gerhard Raabe, Dieter Enders|2016|Synthesis|48|3207|doi:10.1055/s-0035-1561468

CCDC 1474975: Experimental Crystal Structure Determination

Related Article: Uğur Kaya, Pankaj Chauhan, Kristina Deckers, Rakesh Puttreddy, Kari Rissanen, Gerhard Raabe, Dieter Enders|2016|Synthesis|48|3207|doi:10.1055/s-0035-1561468

CCDC 1814040: Experimental Crystal Structure Determination

Related Article: Ying Zhi, Kun Zhao, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Org.Chem.Front.|5|1348|doi:10.1039/C8QO00008E

CCDC 1440552: Experimental Crystal Structure Determination

Related Article: Kun Zhao, Ying Zhi, Xinyi Li, Rakesh Puttreddy, Kari Rissanen and Dieter Enders|2016|Chem.Commun.|52|2249|doi:10.1039/C5CC10057G

CCDC 1831534: Experimental Crystal Structure Determination

Related Article: Qiang Liu, Sun Li, Xiang-Yu Chen, Kari Rissanen, Dieter Enders|2018|Org.Lett.|20|3622|doi:10.1021/acs.orglett.8b01400

CCDC 1864513: Experimental Crystal Structure Determination

Related Article: Qiang Liu, Xiang-Yu Chen, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2018|Angew.Chem.,Int.Ed.|57|17100|doi:10.1002/anie.201810402

CCDC 1889531: Experimental Crystal Structure Determination

Related Article: Qiang Liu, Xiang‐Yu Chen, Sun Li, Kari Rissanen, Dieter Enders|2019|Adv.Synth.Catal.|361|1991|doi:10.1002/adsc.201900065

CCDC 1975968: Experimental Crystal Structure Determination

Related Article: Fabrizio Vetica, Stephen J. Bailey, Mukesh Kumar, Suruchi Mahajan, Carolina von Essen, Kari Rissanen, Dieter Enders|2020|Synthesis|52|2038|doi:10.1055/s-0040-1707472

CCDC 1484545: Experimental Crystal Structure Determination

Related Article: Ugur Kaya, Suruchi Mahajan, Jan-Hendrik Schöbel, Arto Valkonen, Kari Rissanen and Dieter Enders|2016|Synthesis|48|4091|doi:10.1055/s-0035-1562473

CCDC 1442230: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Pankaj Chauhan, Daniel Hack,Arne R. Philipps, Rakesh Puttreddy, Kari Rissanen, Gerhard Raabe, Dieter Enders|2016|Chem.-Eur.J.|22|5123|doi:10.1002/chem.201600515

CCDC 1816580: Experimental Crystal Structure Determination

Related Article: Mukesh Kumar, Pankaj Chauhan, Stephen J. Bailey, Ehsan Jafari, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Org.Lett.|20|1232|doi:10.1021/acs.orglett.8b00175

CCDC 1543566: Experimental Crystal Structure Determination

Related Article: V. Pratap Reddy Gajulapalli, Ehsan Jafari, Dipti Sankar Kundu, Suruchi Mahajan, Anssi Peuronen, Kari Rissanen, Dieter Enders|2017|Synthesis|49|4986|doi:10.1055/s-0036-1590823

CCDC 1561240: Experimental Crystal Structure Determination

Related Article: Xiang-Yu Chen, Sun Li, He Sheng, Qiang Liu, Ehsan Jafari, Carolina von Essen, Kari Rissanen, Dieter Enders|2017|Chem.-Eur.J.|23|13042|doi:10.1002/chem.201703579

CCDC 1555938: Experimental Crystal Structure Determination

Related Article: Sun Li, Xiang-Yu Chen, Qiang Liu, Anssi Peuronen, Kari Rissanen, Dieter Enders|2017|Synthesis|49|4861|doi:10.1055/s-0036-1588509

CCDC 1482605: Experimental Crystal Structure Determination

Related Article: Fabrizio Vetica, Jeanne Fronert, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2016|Synthesis|48|4451|doi:10.1055/s-0035-1562522

CCDC 1413502: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Marcus Blümel, Arne R. Philipps, Ai Wang, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2016|Angew.Chem.,Int.Ed.|55|11110|doi:10.1002/anie.201604819

CCDC 1537523: Experimental Crystal Structure Determination

Related Article: Pankaj Chauhan, Suruchi Mahajan, Uğur Kaya, Anssi Peuronen, Kari Rissanen, and Dieter Enders|2017|J.Org.Chem.|82|7050|doi:10.1021/acs.joc.7b01113

CCDC 1537522: Experimental Crystal Structure Determination

Related Article: Pankaj Chauhan, Suruchi Mahajan, Uğur Kaya, Anssi Peuronen, Kari Rissanen, and Dieter Enders|2017|J.Org.Chem.|82|7050|doi:10.1021/acs.joc.7b01113

CCDC 1446165: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Pankaj Chauhan, Daniel Hack,Arne R. Philipps, Rakesh Puttreddy, Kari Rissanen, Gerhard Raabe, Dieter Enders|2016|Chem.-Eur.J.|22|5123|doi:10.1002/chem.201600515

CCDC 1437740: Experimental Crystal Structure Determination

Related Article: Suruchi Mahajan, Pankaj Chauhan, Marcus Blümel, Rakesh Puttreddy, Kari Rissanen, Gerhard Raabe, Dieter Enders|2016|Synthesis|48|1131|doi:10.1055/s-0035-1560412

CCDC 1437686: Experimental Crystal Structure Determination

Related Article: Tao Shu, Qijian Ni, Xiaoxiao Song, Kun Zhao, Tianyu Wu, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2016|Chem.Commun.|52|2609|doi:10.1039/C5CC09581F

CCDC 1476009: Experimental Crystal Structure Determination

Related Article: Pankaj Chauhan, Suruchi Mahajan, Uğur Kaya, Arto Valkonen, Kari Rissanen and Dieter Enders|2016|Adv.Synth.Catal.|358|3173|doi:10.1002/adsc.201600554

CCDC 1437688: Experimental Crystal Structure Determination

Related Article: Uğur Kaya, Pankaj Chauhan, Daniel Hack, Kristina Deckers, Rakesh Puttreddy, Kari Rissanen, Dieter Enders|2016|Chem.Commun.|52|1669|doi:10.1039/C5CC09592A

CCDC 1527542: Experimental Crystal Structure Determination

Related Article: Lei Wang, Sun Li, Marcus Blümel, Rakesh Puttreddy, Anssi Peuronen, Kari Rissanen, Dieter Enders|2017|Angew.Chem.,Int.Ed.|56|8516|doi:10.1002/anie.201704210

CCDC 1493409: Experimental Crystal Structure Determination

Related Article: Kun Zhao, Ying Zhi, Tao Shu, Arto Valkonen, Kari Rissanen, Dieter Enders|2016|Angew.Chem.,Int.Ed.|55|12104|doi:10.1002/anie.201606947

CCDC 1571777: Experimental Crystal Structure Determination

Related Article: Xiang-Yu Chen, Jia-Wen Xiong, Qiang Liu, Sun Li, He Sheng, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Angew.Chem.,Int.Ed.|57|300|doi:10.1002/anie.201708994

CCDC 1589299: Experimental Crystal Structure Determination

Related Article: Ehsan Jafari, Pankaj Chauhan, Mukesh Kumar, Xiang-Yu Chen, Sun Li, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Eur.J.Org.Chem.|2018|2462|doi:10.1002/ejoc.201800034

CCDC 1574958: Experimental Crystal Structure Determination

Related Article: Qingong Li, Kun Zhao, Anssi Peuronen, Kari Rissanen, Dieter Enders, Yefeng Tang|2018|J.Am.Chem.Soc.|140|1937|doi:10.1021/jacs.7b12903

CCDC 1572983: Experimental Crystal Structure Determination

Related Article: Uğur Kaya, Pankaj Chauhan, Suruchi Mahajan, Kristina Deckers, Arto Valkonen, Kari Rissanen, Dieter Enders|2017|Angew.Chem.,Int.Ed.|56|15358|doi:10.1002/anie.201709224

CCDC 1844760: Experimental Crystal Structure Determination

Related Article: Tao Shu, Sun Li, Xiang-Yu Chen, Qiang Liu, Carolina von Essen, Kari Rissanen, Dieter Enders|2018|Chem.Commun.|54|7661|doi:10.1039/C8CC04145H

CCDC 1534754: Experimental Crystal Structure Determination

Related Article: Xiang-Yu Chen, Qiang Liu, Pankaj Chauhan, Sun Li, Anssi Peuronen, Kari Rissanen, Ehsan Jafari, Dieter Enders|2017|Angew.Chem.,Int.Ed.|56|6241|doi:10.1002/anie.201702881

CCDC 1510190: Experimental Crystal Structure Determination

Related Article: Simon Dochain, Fabrizio Vetica, Rakesh Puttreddy, Kari Rissanen and Dieter Enders|2016|Angew.Chem.,Int.Ed.|55|16153|doi:10.1002/anie.201610196

CCDC 1542995: Experimental Crystal Structure Determination

Related Article: Mukesh Kumar, Pankaj Chauhan, Arto Valkonen, Kari Rissanen, and Dieter Enders|2017|Org.Lett.|19|3025|doi:10.1021/acs.orglett.7b01322