129752-69-8Relevant articles and documents
Resolution of racemic rhododendrol by lipase-catalyzed enantioselective acetylation
Yuasa, Yoshifumi,Shibuya, Shiroshi,Yuasa, Yoko
, p. 1469 - 1475 (2003)
Both (R)- and (S)-enantiomers of rhododendrol were prepared in high enantiomeric exess by lipase from Pseudomonas cepacia (Amano PS)-catalyzed acetylation of racemic 1 with vinyl acetate at room temperature. Especially, in the case of using acetonitrile as the solvent, by-products 4 and 5 were minimized.
Scalable green approach toward fragrant acetates
Puchl'Ová, Eva,Szolcsányi, Peter
, (2020/08/07)
The advantageous properties of ethylene glycol diacetate (EGDA) qualify it as a useful substitute for glycerol triacetate (GTA) for various green applications. We scrutinised the lipase-mediated acetylation of structurally diverse alcohols in neat EGDA furnishing the range of naturally occurring fragrant acetates. We found that such enzymatic system exhibits high reactivity and selectivity towards activated (homo) allylic and non-activated primary/secondary alcohols. This feature was utilised in the scalable multigram synthesis of fragrant (Z)-hex-3-en-1-yl acetate in 70percent yield. In addition, the Lipozyme 435/EGDA system was also found to be applicable for the chemo-selective acetylation of (hydroxyalkyl) phenols as well as for the kinetic resolution of chiral secondary alcohols. Lastly, its discrimination power was demonstrated in competitive experiments of equimolar mixtures of two isomeric alcohols. This enabled the practical synthesis of 1-pentyl acetate isolated as a single product in 68percent yield from the equimolar mixture of 1-pentanol and 3-pentanol.
Asymmetric synthesis of enantiomerically pure zingerols by lipase-catalyzed transesterification and efficient synthesis of their analogues
Kitayama, Takashi,Isomori, Sachiko,Nakamura, Kaoru
, p. 621 - 627 (2013/07/19)
The achiral zingerone 1, readily available from ginger, can be easily transformed into chiral derivatives. Zingerol 2, a reduced product of zingerone 1 is expected to be an important new medicinal lead compound. We have achieved a concise synthesis of optically active zingerol (R)-2 and (S)-2 by the lipase-catalyzed stereoselective transesterification of racemic 2. Under the optimized conditions, a lipase from Alcaligenes sp. (Meito QLM) and vinyl acetate in i-Pr2O or hexane at 35 C within 1 h gave the alcohol (S)-2 and the acetate (R)-9 with high enantioselectivity without producing acetylated by-products. Since optically active (S)-2 and (R)-9 were obtained through lipase-catalyzed transesterification, other enantiomerically pure novel compounds could all be synthesized.
Part 148 in the series "studies on novel synthetic methodologies:" Selective acetylation of alcohols, phenols and amines and selective deprotection of aromatic acetates using silica-supported phosphomolybdic acid
Das, Biswanath,Thirupathi, Ponnaboina,Kumar, Rathod Aravind,Laxminarayana, Keetha
, p. 2677 - 2683 (2008/09/19)
An environmentally friendly silica-supported phosphomolybdic acid was found to be a highly efficient catalyst for the selective acetylation of alcohols, phenols and amines in the absence of any solvent and also for the chemoselective deprotection of aromatic acetates under very mild conditions. This method has been used for the protection of the hydroxy groups as well as for the deprotection of the acetates of several naturally occurring bioactive phenolic compounds. The catalyst can be easily recovered and reused.
