36874-53-0Relevant articles and documents
Homochiral (R)- and (S)-1-heteroaryl- and 1-aryl-2-propanols via microbial redox
Fogagnolo, Marco,Giovannini, Pier Paolo,Guerrini, Alessandra,Medici, Alessandro,Pedrini, Paola,Colombi, Nicola
, p. 2317 - 2327 (2007/10/03)
Preparation of various heteroaryl propanols 2a-g and of the corresponding propanones 3a-g as starting materials for microbial redox is described. The kinetic resolution of the racemic propanols 2a-g is obtained via oxidation with Pseudomonas paucimobilis and Bacillus stearothermophilus [(R)-alcohols, ee 74-100%]. Similar results are achieved with 3-(2- hydroxypropyl)trifluoromethylbenzene 7 (44%, ee 100% of the (R)-alcohol 6). The reduction of the propanones 3a-d and 3g with baker's yeast and other fungi gives the (S)-alcohols (ee 100%). The pure (S)-alcohols are also obtained by reduction of 1-[3-(trifluoromethyl)phenyl]-2-propanone 7. 1- [(4,4-Dimethyl)-2-(Δ2)oxazolinyl]-2-propanone 3e and 1[2-(Δ2)- thiazolinyl)-2-propanone 3f are not reduced. The heterocyclic rings of (S)- 5-(2-hydroxypropyl)-3-methylisoxazole 2d and of (S)-2-(2-hydroxypropyl)-4- methylthiazole 2g are deblocked to the homochiral enamino ketone 8 (78%) and to the protected β-hydroxy aldehyde 9 (73%), respectively. The (R)-3-(2- hydroxypropyl)trifluoromethylbenzene 6 is transformed into the homochiral precursor of (S)-fenfluramine 10 (overall yield 65%).
Action of (2-Benzothiazolyl) Methyllithium with Organic Polar Functions
Costa, Maria Virginia,Brembilla, Alain,Roizard, Denis,Lochon, Pierre
, p. 1541 - 1544 (2007/10/02)
(2-Benzothiazolyl) methyllithium reacts quickly at low temprature (-78 deg C) with a variety of organic electrophiles like aldehydes, ketones, carboxylic esters, nitriles and acylchlorides.Such reactions lead to an easy introduction of alcohol, keto-enol
Process for the preparation of 2-substituted benzothiazoles
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, (2008/06/13)
Process for the preparation of benzothiazoles of the formula (1) STR1 wherein R denotes an alkylC1-C6 or an a kenylC2-C6 group which can be substituted by alkoxyC1-C4, acyl, phenyl, chlorophenyl, bromophenyl, alkylC1-C4 phenyl, alkoxyC1-C4 -phenyl or nitrophenyl groups or halogen atoms, or denotes a phenyl group which can be substituted by alkylC1-C4, alkoxyC1-C4, carboxyl-, --COO-alkylC1-C4, cyano or nitro or halogen atoms, and X and Y each denote a hydrogen or halogen atom or an alkylC1-C4, alkoxyC1-C4 or nitro group, or together denote a fused benzene ring, wherein the salts of the corresponding 2-mercaptophenylureas of the formula (5) STR2 in which X and Y have the stated meansings and Me denotes an alkali metal atom or the equivalent amount of an alkaline earth metal atom, which salts are obtainable as intermediate compounds in a known manner by reacting 2-aminobenzothiazoles of the general formula (4) STR3 in which X and Y have the abovementioned meanings, with alkali metal or alkaline earth metal hydroxides in an anhydrous or virtually anhydrous solvent, are treated, in the isolated form or in suspension in the ring-opening mixture, with an acylating agent of the formula (3) in which R has the abovementioned meaning and Z represents a halogen atom or the group STR4 wherein R has the stated meaning, or with diketene at temperatures from 0° C. to 200° C.
REACTION OF YNAMINO KETONES WITH BIFUNCTIONAL REAGENTS
Ostroumov, I. G.,Tsil'ko, A. E.,Maretina, I. A.,Petrov, A. A.
, p. 1049 - 1055 (2007/10/02)
The reaction of 4-dialkylamino-3-butyn-2-ones with nitrogen-containing bifunctional reagents (ethylenediamine, ethanolamine, o-aminophenol, o-aminothiophenol, and o-phenylenediamine) was studied.In all cases except o-phenylenediamine the five-membered het
