Re<sub>2</sub>O<sub>7</sub>-catalyzed reaction of hemiacetals and aldehydes with <i>O</i>-, <i>S-,</i> and <i>C</i>-nucleophiles
作者:Wantanee Sittiwong、Michael W Richardson、Charles E Schiaffo、Thomas J Fisher、Patrick H Dussault
DOI:10.3762/bjoc.9.174
日期:——
monothioacetalization and allylation of hemiacetals. The reactions, which take place under mild conditions and at low catalyst loadings, can be conducted using hemiacetals, the corresponding O-silyl ethers, and, in some cases, the acetal dimers. Aldehydes react under similar conditions to furnish good yields of dithioacetals. Reactions of hemiacetals with nitrogen nucleophiles are unsuccessful. 1,2-Dioxolan-3-ols
Re(VII) 氧化物催化半缩醛的缩醛化、单过氧缩醛化、单硫代缩醛化和烯丙基化。在温和条件和低催化剂负载下发生的反应可以使用半缩醛、相应的 O-甲硅烷基醚以及在某些情况下使用缩醛二聚体进行。醛在类似条件下反应以提供良好收率的二硫缩醛。半缩醛与含氮亲核试剂的反应不成功。1,2-Dioxolan-3-ols(过氧半缩醛)进行 Re(VII) 促进的醚化,但不进行烯丙基化。氢过氧缩醛(1-烷氧基氢过氧化物)在 Re2O7 或布朗斯台德酸存在下进行醇盐基团的选择性交换。