Search results for " molecule"

Diels-Alder reactions of 1-phenylpyrano[3,4-b]indol-3-ones with alkynes: New functionalized carbazoles

1990

3-Indolylalkanoic acids 2 react with benzoic acid anhydride under catalysis of Et2O - ZnCl2 and mild conditions to furnish the 1-phenyl-substituted pyrano[3,4-b]indol-3-ones 1c, 1d, and 3a, 3b. Products 1c, 1d, and 3b may be converted into the novel functionalized carbazoles 4 and 5 by reaction with acceptor-substituted alkynes.

Polycondensed nitrogen heterocycles. Part24. Pyrrolo[3,4-c]isoquinolinone by thermal rearrangement of a pyrrolylbenzotriazinone

1992

Rearrangement under acidic conditions of the pyrrolylbenzotriazinone 7 afforded the pyrrolylbenzamides 10 and 11. By thermal rearrangement instead, the first fully aromatic derivative of the pyrrolo[3,4-c]isoquinoline ring system 9 was obtained.

Darstellung, Kristallstruktur und Wirkung von 2-Methyl-3-(4-oxo-3-phenyl-thiazolidin-2-ylidenamino)-4-(3H)-chinazolinon

1984

Quinazolinones. 1. Preparation, crystal structure and action of 2-methyl-3-(4-oxo-3-phenyl-thiazolidine-2-ylidenamino)-4-(3H)- quinazolinone.

Synthesis and structural characterization of cis- and trans-fused 4a,5,6,7,8,8a-hexahydro-2H,4H-1,3-benzodithiines and their 2-methyl and 2,2-dimethy…

2002

Both cis- and trans-fused 4a,5,6,7,8,8a-hexahydro-2H,4H-1,3-benzodithiine together with their 2-methyl and 2,2-dimethyl derivatives were prepared as racemates from the appropriate dithiols obtained via multistep syntheses. The products were characterized by 1 H and 13 C NMR, mass spectrometry, and for two of the cis-fused compounds by X-ray diffraction. 1 H, 1 H vicinal coupling constants indicated that all compounds attain chair-chair conformations as their predominant conformations. All three trans-fused isomers exist in totally biased chair-chair conformations and are essentially conformationally locked, whereas the cis-fused compounds are conformationally mobile and can potentially atta…

Reaktivitäut und reaktionswege von methylsubstituierten bisindolylcarbenium-ionen

1987

Methyl substituted bisindolylcarbenium ions 1 react with some O- and C-nucleophiles regioselectively. The cations 1b, 1c yield with hydroxide ions the tetraindolyldimethyl ether 4 and with methoxide ions the bisin-dolylmethoxymethanes 5. Compounds 1a, 1b, 1c react with several methylindoles to isomeric bis- and trisin-dolylmethanes. An electrophilic reactivity order of cations 1 can be derived supporting on the experimental results.

Revision of Na 2 A1Σ+u state molecular constants by polarization labeling spectroscopy

1997

ABSTRACT. This paper contains the analysis of the A1 of Na2 based on the data obtained from thepolarization labeling spectroscopy experiment on the A' —X' transition. A set of Dunham coefficients is derived, which describes the A state in the wide range of v and J 126) quantum numbers and reproduces the positions of unperturbed rotational lines in the A-X band system towithinO.1 cm'.1. INTRODUCTION.We report' new analysis of the A' state based on the data obtained from polarization labelingspectroscopy (PLS) experiment"2, based on V-type optical—optical double resonance scheme, on the 1 : ' ; band system of sodium dimer. The diatomic alkali molecules, with their simple electronic configurat…

Generation of hexahydroazulenes

2009

(Z)-Cyclodec-1-en-6-yne (3) generates three conjugated hexahydroazulenes 3→1k→1c, 1l under FVP conditions, whereas flash vacuum pyrolysis (FVP) of cyclodecyne (2) leads to 1,2,9-decatriene (9). We attribute the different thermal behavior of 2 (ring opening) and 3 (ring closure) to different transannular interactions. Altogether 22 constitutional isomers of hexahydroazulene should exist; three new isomers (1k, 1l, and 1m) are presented here, ten were described earlier, but the reinvestigation of the dehydration route of bicyclic alcohol 11 showed that one of the ten structures has to be revised.

The reaction of enones with electrophiles

2010

Triazolopyridines. Part 9. The synthesis of7-amino(1,2,3)triazolo(1,5-a)pyridines

1989

Abstract Regiospecific lithiation of (1,2,3) triazolo(1,5-a)pyridines (1) and (4) with subsequent reaction with styryl azide gave small yields of the 7-aminotriazolopyridines (6) and (7). A longer larger scale synthesis of compounds (6) and (7) is described giving overall yields of 17 and 25%, starting from 2-amino-6-methyl (9) or 2-amino-6-ethyl pyridine (19).

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.