A Novel Synthetic Methods Through Alpha, Beta-Epoxy Sulfoxides and Related Compounds

通过氯醇和α，β-环氧亚硫醚将1-氯代烷基芳基亚砜与羰基化合物加成，得到了一种新方法。用LiClO_4处理α，β-环氧亚砜得到了α，β-不饱和酮，这些酮分三步转化为烯丙基环氧化物，总收率很高。这些烯丙基环氧化物用LDA处理，以高产率得到螺环连接的亚甲基环丙烷。然后将这些亚甲基环丙烷转化为稠合的3-甲基呋喃。氯醇的热消除得到定量的氯乙烯，再用臭氧氧化得到高产率的α-羟基羧酸及其衍生物。该方法发展为利用光学活性1-氯丁基对甲苯基亚砜不对称合成这两种化合物。氯乙烯经环氧化得到氯氧烷，再与各种亲核试剂反应，以较高的产率得到α-羟基α‘-取代酮。用过量的n-BuLi处理氯乙烯可得到总收率高的丙叉醇和乙炔二醇。上述氯醇的Swern氧化反应得到了α-卤代α-烷基-β-酮亚砜。这些化合物用乙基溴化镁处理，以相当高的产率得到了α-卤代酮。

A novel methods are developed from the addition of 1-chloroalkyl aryl sulfoxides with carbonyl compounds through the chloroalcohols and alpha, beta-epoxy sulfoxides. Treatment of the alpha, beta-epoxy sulfoxides with LiClO_4 gave alpha, beta-unsaturated ketones, which were converted to allylic epoxides in three steps in good overall yields. These allylic epoxides were treated with LDA to afford spiro-linked methylenecyclopropanes in high yields. These methylenecycopropanes were then converted to fused 3-methylfurans. Thermal elimination of the chloroalcohols gave vinyl chlorides in quantitative yields, which were oxidized with ozone to afford alpha-hydroxycarboxylic acids and their derivatives in good yields. This method was developed to an asymmetric synthesis of them using optically active 1-chlorobutyl p-tolyl sulfoxide. Epoxydation of the vinyl chlorides gave chlorooxylanes, Which were reacted with various nucleophiles to afford alpha-hydroxy alpha'-substituted ketones in good yields. Treatment of the vinyl chlorides with excess n-BuLi afforded propargylic alcohols and acetylene diols in high overall yields. Swern oxidation of the above mentioned chloroalcohols gave alpha-halo alpha-alkyl beta-keto sulfoxides. These were treated with EtMgBr to give alpha-halo ketones in quite high yields.