Search results for "METHANE"

Photochemical Nitration by Tetranitromethane. Part XL. Regiochemistry of Trinitromethyl Attachment in the Photolysis of Benzofuran with Tetranitromet…

1997

Synthesis of 1,3-Oxazolidines and 1,3-Dioxolanes by Reaction of (2R, 3R)-3-Methylamino-3-phenyl-1,2-propanediol with Electrophiles

2003

Abstract The chemoselective reaction of (2R, 3R)-3-methylamino-3-phenyl-1,2-propanediol 1 with dimethoxypropane and dichloromethane under different conditions are reported as useful preparative procedures, for the synthesis 1,3-oxazolidines and 1,3-dioxolanes.

ChemInform Abstract: Modular Access to 9,9-Spirobifluorenes by Oxidative Coupling Using Molybdenum Pentachloride.

2013

The reactions of diarylfluorenes and substrates (III) or (V) result in formation of spirobifluorenes and fluorene derivatives.

Selective C-H Activation of Methoxy Groups in a Three-Component Photoreaction.

2015

Surprisingly, the photocatalytic activation of ethers by H-abstraction and addition of the generated radicals to iminium ions formed in situ from aldehydes and anilines predominantly yielded the products of methoxy activation for dimethoxymethane and 1,2-dimethoxyethane. Various anilines and aromatic as well as aliphatic aldehydes are suitable reaction partners for this three-component photoreaction (Porta-type process) which also provides a simple access to 1,2-aminoalcohols.

ChemInform Abstract: Selective C-H Activation of Methoxy Groups in a Three-Component Photoreaction.

2016

Surprisingly, the photocatalytic activation of ethers by H-abstraction and addition of the generated radicals to iminium ions formed in situ from aldehydes and anilines predominantly yielded the products of methoxy activation for dimethoxymethane and 1,2-dimethoxyethane. Various anilines and aromatic as well as aliphatic aldehydes are suitable reaction partners for this three-component photoreaction (Porta-type process) which also provides a simple access to 1,2-aminoalcohols.

Generation of Stereocenters Around a C3-Symmetric Cyclotriveratrylene Crown

2012

The oxidation of racemic methylthio-substituted C3-symmetric cyclotriveratrylene (CTV) 2 produces the corresponding trisulfoxides 3 as follows. Oxidation with m-chloroperoxybenzoic acid (m-CPBA) in dichloromethane leads to the formation of a distribution of the four possible diastereomers that is relatively close to the statistical outcome, in which the C3-symmetric stereoisomers are the minor species. In contrast, the optically active Davis reagent [oxaziridine (+)-4] in carbon tetrachloride at room temperature leads to a biased (73 %) distribution in favor of the C3-symmetric MRRR/PSSS diastereomer of 3 with 56 % ee (PSSS enantiomer according to the model of Davis). Interestingly, when th…

Halogen bond preferences of thiocyanate ligand coordinated to Ru(II) via sulphur atom

2017

Halogen bonding between [Ru(bpy)(CO)2(S-SCN)2] (bpy = 2,2’-bipyridine), I2 was studied by co-crystallising the metal compound and diiodine from dichloromethane. The only observed crystalline product was found to be [Ru(bpy)(CO)2(S-SCN)2]⋅I2 with only one NCS⋅⋅⋅I2 halogen bond between I2 and the metal coordinated S atom of one of the thiocyanate ligand. The dangling nitrogen atoms were not involved in halogen bonding. However, computational analysis suggests that there are no major energetic differences between the NCS⋅⋅⋅I2 and SCN⋅⋅⋅I2 bonding modes. The reason for the observed NCS⋅⋅⋅I2 mode lies most probably in the more favourable packing effects rather than energetic preferences between …

Rhodium catalyzed oxidative coupling of salicylaldehydes with diazabicyclic olefins: a one pot strategy involving aldehyde C–H cleavage and π-allyl c…

2013

An efficient one pot strategy for the synthesis of cyclopentene fused chromanone derivatives through the direct oxidative coupling of salicylaldehydes with bicyclic olefins in the presence of a rhodium-copper catalyst system is described. This is the first report on the ring opening-ring closing of bicyclic hydrazines via metal catalyzed oxidative coupling reaction.

Modular Approach to 9-Monosubstituted Fluorene Derivatives Using Mo(V) Reagents.

2016

Oxidative coupling using molybdenum(V) reagents provides fast access to highly functionalized 9-monosubstituted fluorenes. This synthetic approach is highly modular, is high yielding, and tolerates a variety of labile moieties, e.g. amides or iodo groups. The established protocol leads to promising precursors for pharmacologically important analogues of melatonin.

Electrochemical monitoring of the oxidative coupling of alkynes catalyzed by triphenylphosphine gold complexes

2012

Electrochemical monitoring of the oxidative coupling of alkynes in the homogeneous phase through catalytic cycles involving triphenylphosphine gold complexes and selectfluor as oxidant reveals that at least two gold species in +3 and +1 oxidation states are implicated. Electrochemically driven homocoupling of terminal alkynes using molecular oxygen as the oxidant can be performed using such catalysts. Keywords: Gold catalysis, Oxidative coupling of alkynes, Oxygen, Voltammetry