光学活性N-肉桂酰R(S)-4-异丙基四氢噻唑-2-硫酮的合成及其 量子化学的研究

用KBH~4,CaCl~2为还原使D及L缬氨酸甲酯还原得到光学活性产物R-3-甲基-2-氨基丁醇(2a)及S-3-甲基-2-氨基丁醇(2b)。2a,2b同CS~2在KOH存在下反应得到(R)-4-异丙基四氢噻唑-2-硫酮(3a)及(S)-4-异丙基四氢噻唑-2-硫酮(3b)。肉桂酰氯分别同3a及3b在Et~3N存在下反应得到N-肉桂酰(R)-4-异丙基四氢噻唑-2-硫酮(4a)及N-肉桂酰(S)-4-异丙基四氢噻唑-2-硫酮(4b)。用半经验的量子化学PM3方法研究了反应物和产物的电子结构,得到了产物的最优构型和电荷键序分布以及反应焓变。

Study on synthesis and quantum chemistry of R(S)-N-cinnamyl-4- isopropyl thiazolidine-2-thione

Aminoalcohols R-3-methyl-2-amino-butyl alcohol 2a α]^2^0~D -15.18° , S-3-methyl-2-amino-butyl alcohol 2b α]^2^0~D +16.96° were prepared by the reduction of D or L-valine methyl ester. The reduction was carried out the KBH~4 and CaCl~2. R-4- isopropylthiazolidine-2-thione 3a, α]^2^0~D +37.00° and S-4- isopropylthiazolidine-2-thione 3b, α]^2^0~D -36.90° were obtained by refluxing a solution of R or S-3-methyl-2-aminobutylalcohol, CS~2 and KOH. The R-N-cinnamyl-4-isopropyl thiazolidine-2-thione 4a, α] ^2^0~D -169.72° and S-N-cinnamyl-4-isopropylthiazolidine-2- thione 4b, α]^2^0~D +173.20° was easily prepared by dehydro chlorination between cinnamyl chloride and R or S-4-isopropylthia- zolidine-2- thione under the presence of Et~3N. The electronic structure of products and reactants were studied by molecular orbital PM3 method. The reaction enthalpies and optimized configuration for products were obtained.