Synthesis, Olfactory Evaluation, and Determination of the Absolute Configuration of the 3,4-Didehydroionone Stereoisomers
作者:Stefano Serra、Claudio Fuganti、Elisabetta Brenna
DOI:10.1002/hlca.200690109
日期:2006.6
(Scheme 3). The latter compounds were used as starting materials to prepare the 3,4-didehydro-γ-ionones (+)- and (−)-6 and the 3,4-didehydro-7,8-dihydro-γ-ionones (+)- and (−)-7 in enantiomer-enriched form. The absolute configuration of (+)-12b was determine by chemical correlation with (+)-(6S)-γ-ionone ((+)-3) and with (−)-(6S)-α-ionone ((−)-1) therefore allowing to assign the (S)-configuration to (+)-6
3,4-二氢二氢紫罗兰酮异构体4,(+)- 6和(-)- 6的合成以及3,4-二氢二氢-7,8-二氢紫罗兰酮异构体5,(+)- 7和(-)-的合成从可商购的外消旋α-紫罗兰酮(1)开始完成图7。它们的外消旋形式制备4 - 7首先被平均的一些化疗和区域选择性反应(的实现方案1和2)。对映体和非对映体选择性脂肪酶介导的4-羟基-γ-紫罗兰酮的动力学乙酰化(10a / 10b)提供4-羟基-γ-紫罗兰酮(+)- 10a /(±)-10b和(+)-4-(乙酰氧基)-γ-紫罗兰酮((+)12b)(方案3)。后一种化合物用作制备3,4-didehydro- γ-紫罗兰酮(+)-和(-)- 6和3,4-didehydro-7,8- dihydro - γ-紫罗兰酮(+)的原料-和(-)- 7为对映异构体富集形式。(+)- 12b的绝对构型是通过与(+)-(6 S)-γ-紫罗兰酮((+)- 3)和(-)-(6