作者:M. Tomoeda、M. Inuzuka、T. Furuta、M. Shinozuka、T. Takahashi
DOI:10.1016/0040-4020(68)88046-9
日期:——
and its 4-substituted analogs, Me, OH, OMe, OAc, Cl, Br, SH, SAc, S-S-bis and S-bis, are tabulated and the deshielding effect of alkylthio group is found to be more than 1 ppm which is the srongest among these various functions. The unique deshielding effect of alkylthio function is shown to be general by examination of 2-ethylthio-3,5,5-trimethylcyclohex-2-enone and its 2-substituted analogs.
在4-乙基硫代胆碱-4-en-3-one,17β-乙酰氧基-4-乙基硫代雄酮-4-en-3-one,16α,17α,-环氧-4-的NMR光谱中,以τ6·22为中心的双峰观察到乙硫基-4-烯-3,20-二酮和17α-羟基-和17α-乙酰氧基-4-乙硫基-4-烯-3,20-二酮,并归因于AB型四重奏的一半(J= 14·5 c / s)由6-亚甲基质子产生。推测分配给C06赤道质子的双峰的异常大的下场偏移是由于C-4处乙硫基官能团的屏蔽作用所致。胆甾烯4-en-3-one及其4取代的类似物Me,OH,OMe,OAc,Cl,Br,SH,SAc,SS-bis和S-bis中的6α质子的化学位移为如表1所示,发现烷硫基的脱屏蔽作用大于1ppm,这在这些各种功能中是最错误的。通过检查2-乙基硫基3,5,5-三甲基环己-2-烯酮及其2-取代的类似物,证明了烷硫基官能团的独特的脱屏蔽作用是普遍的。