Сообщение
Shlavik » Вт июн 16, 2009 2:47 pm
вот абстракт почитайте и исчите друзей в Шанхае!
Regio- and stereo-selective bioreduction of diketo-n-butylphosphonate by baker's yeast. Wang, Ke; Li, Jin-Feng; Yuan, Cheng-Ye; Li, Zu-Yi. Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, Peop. Rep. China. Chinese Journal of Chemistry (2002), 20(11), 1379-1387. Journal written in English. CAN 138:221642
Abstract
Regio- and stereoselective bioredn. of diketo-n-butylphosphonates, for example CH3C(O)C(O)CH2P(O)(OEt)2, by bakers' yeast yielded a mixt. of optically active hydroxyketo-n-butylphosphonates, (S)-(+)-CH3CH(OH)C(O)CH2P(O)(OEt)2 (1) (58% yield, 90% ee) and (-)-CH3C(O)C(OH)CH2P(O)(OEt)2 (2) (17% yield, 55% ee). Isomers 1 and 2 were sepd. by column chromatog. Hydroxyketo-n-butylphosphonate 1 was used as a chiron for prepn. of a,b-unsatd. ketones, for example trans-(S)-(+)-PhCH:CHC(O)CH(OH)CH3 (56% yield), via Horner-Wadsworth-Emmons reaction with benzaldehydes, such as PhCHO. Similarly, CF3C(O)CH2C(O)CH2P(O)(OEt)2 was reduced regio- and stereoselectively by bakers' yeast to (+)-CF3C(OH)CH2C(O)CH2P(O)(OEt)2 (41% yield, 91% ee), which reacted with 4-Me-C6H4CHO, yielding trans-(+)-4-Me-C6H4CH:CHC(O)CH2C(OH)CF3 (3) (66% yield). The structure of 3 was established by X-ray diffraction.
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