The benzoxathiazine 2-oxide derivatives (2a–f) were prepared by reaction of the aminophenols (1a–f) with thionyl chloride in good yields. Equilibrium of 2a (R1=α-C10H7, R2=CH3) with hydrogen chloride and subsequent reaction with phenylmagnesium bromide followed by action of methyl- or butyllithium gave (S)-(−)-4a or (S)-(−)-4b with high enantiomeric excess, respectively.
                                    苯并恶
噻嗪 2-氧化物衍
生物 (2a-f) 是通过
氨基苯酚 (1a-f) 与亚
硫酰氯以良好的收率反应制备的。2a (R1=α-
C10H7, R2=
CH3) 与
氯化氢的平衡,随后与
苯基溴化镁反应,然后与甲基-或丁基
锂作用,得到 (S)-(-)-4a 或 (S)-(-)- 4b 分别具有高对映体过量。