Preparation of Sulfur-Containing Optically Active Secondary Alcohols Based on<i>Pichia farinosa</i>-Catalyzed<i>anti</i>-Prelog-Rule Reduction as the Key Step
A Pichia farinosa IAM 4682 mediated reduction of sulfur containing ketones afforded secondaryalcohols with (R)-absolute configuration. For example, 4-(phenylthio)-2-butanone and 4-(phenylsulfonyl)-2-butanone afforded (R)-4-(phenylthio)-2-butanol (91%ee) in 90% yield and (R)-4-(phenylsulfonyl)-2-butanol (97%ee) in 94% yield, respectively. In the case that the ee of the product was not satisfactory
Pichia farinosa IAM 4682 介导的含硫酮还原得到具有 (R)-绝对构型的仲醇。例如,4-(苯硫基)-2-丁酮和4-(苯磺酰基)-2-丁酮以90%的产率提供(R)-4-(苯硫基)-2-丁醇(91%ee)和(R)- 4-(苯磺酰基)-2-丁醇(97%ee)分别为94%产率。在产品的ee不令人满意的情况下,任何污染的(S)-对映体被玫瑰色红球菌IFO 15564选择性氧化,留下纯的(R)-对映体。进一步检查了粉状毕赤酵母介导的还原和玫瑰色红球菌介导的氧化的底物特异性。
A new practical synthesis of (+)-grandisol from (+)-citronellol using an intramolecular carbenoid cyclization
作者:Hugo J. Monteiro、Julio Zukerman-Schpector
DOI:10.1016/s0040-4020(96)00175-5
日期:1996.3
A new practical 10 step synthesis of (1S,2R)-2-acetyl-1-methylcyclobutaneacetic acid 15 is reported, which has as a key step a rhodium catalyzed intramolecular carbenoid cyclization of the α-diazo-β-ketosulfone 5, readily available from (+)-citronellol 2. Since 15 has already been converted into (+)-grandisol 1, the major pheromone of the cotton boll-weevil Anthonomus grandis, the described preparation