Reactions of ortho oxy-substituted benzyl and phenacyl bromides in dimethyl sulphoxide
作者:J.A. Donnelly、P.A. Kerr、P. O'Boyle
DOI:10.1016/0040-4020(73)80223-6
日期:1973.1
bromides and tosylates oxidatively rearrange in moist dimethyl sulphoxide to o-hydroxybenzyl esters; o-acetoxy- and o-benzoyloxy- phenacyl bromides rearrange to mixtures of 2-hydroxycoumaran-3-ones and o-hydroxyphenacyl esters; o-hydroxyphenacyl bromides also yield 2-hydroxycoumaran-3-ones, together with o-hydroxyphenacyl alcohols. 2-Acetoxybenzaldehyde is reductively rearranged by sodium borohydride to o-hydroxybenzyl
A Synthetic Protocol for the Construction of Chroman‐Spiroquinazolin(thi)one Framework via a Metal‐Free, Three‐Component, Domino, Double Annulations
作者:Lingfeng Wang、Song Li、Xuqiong Xiao、Weiming Xu、Pengfei Zhang、Yongmin Ma
DOI:10.1002/adsc.202101324
日期:2022.2.15
A three-component domino approach for the synthesis of chroman-spiroquinazolin(thi)ones is described. It involves a condensation of 2-aminoacetophenones and iso(thio)cyanates followed by a hetero-Diels-Alder annulation with 2-hydroxybenzyl alcohol derivatives. The reaction exhibits a broad substrate scope under a metal-free catalytic condition.
Enantioselective Syntheses of Spiroketals via a Tandem Reaction of Cu(I)-Catalyzed Cycloetherification and Hydrogen-Bond-Induced [4 + 2] Cyclization
作者:Tian Tian、Liqi Li、Jijun Xue、Jie Zhang、Ying Li
DOI:10.1021/acs.joc.5b00384
日期:2015.4.17
A tandem reaction consisting of a copper(I)-catalyzed cycloetherification and a hydrogen-bond-induced inverse-electron-demand oxa-DielsAlder cycloaddition was performed from chiral propargyl alcohol, generating several kinds of optically pure [5, 6] spiroketals in excellent stereoselectivities and yields. The investigation on mechanism found that the cyclization prompted by a hydrogen bond not only improved the efficiency but also determined the diastereoselectivity.
Auwers; Buettner, Justus Liebigs Annalen der Chemie, 1898, vol. 302, p. 145