Diastereodivergent Synthesis of
<i>Syn</i>
‐ and
<i>Anti</i>
‐9‐Hydroxyhomoisoflavanone and its Application to the Total Syntheses of (±)‐Homoferrugenone and (±)‐Portulacanone F
作者:Sanha Lee、Sangil Kwon、Joonseong Hur、Seung‐Yong Seo
DOI:10.1002/adsc.202200642
日期:2022.10.18
The diastereodivergent synthesis of syn- and anti-9-hydroxyhomoisoflavanone from various chromones and carbaldehydes is described. The synthetic approaches involving the reductive aldol reaction or the Morita-Baylis-Hillman reaction followed by syn-selective 1,4-reduction provide both diastereomers of β-hydroxy chroman-4-ones in 51–98% yield with anti (2 : 1–16 : 1 anti/syn) or 22–80% yield with syn
描述了从各种色酮和甲醛合成顺-和抗-9-羟基高异黄酮的非对映发散合成。涉及还原性羟醛反应或 Morita-Baylis-Hillman 反应以及顺式选择性 1,4-还原的合成方法以 51-98% 的产率提供了β-羟基 chroman-4-ones 的两种非对映异构体和抗(2:1 –16 : 1 anti / syn ) 或 22–80% syn (5 : 1–48 : 1 syn / anti) 非对映选择性。通过第一次全合成阐明了围绕两种 9-羟基高异黄酮、高铁酮和马齿苋 F 立体化学的模糊性。
Reactivity of α-arylidene benzoheteracyclanone dibromides toward azide ion: an effective approach to 3-(α-substituted-benzyl)chromones and -1-thiochromones
dibromides of 3-arylidenechromanones and -1-thiochromanones with sodium azide resulted in the formation of 3-(α-azidobenzyl)chromones and -1-thiochromones whereas dibromides having no antiperiplanar vicinal hydrogen in the ring such as flavanone, 1-thioflavanone and benzosuberone derivatives afforded only the parent enones by bromine elimination. Evidence supported the intermediacy of 3-(α-bromobenzyl)chromones
The reaction of chromone-derived cyclic Morita–Baylis–Hillman alcohols with amines catalyzed by In(OTf)3 in a one pot process was developed for the convenient and efficient synthesis of 2-substituted-3-aminomethylenechromans. The tandem allylic amination/chromen ring-opening/Michael cyclization reactions were involved in this protocol.