The addition of Grignardreagents to ketones is significantly enhanced by cerium chloride with remarkable suppression of side reactions, particularly enolization. Some esters, which are prone to side reactions, also react readily with Grignardreagents in the presence of cerium chloride to give normal reaction products in reasonable to high yields.
Alkyl-, Aryl-, Vinyl-, and Heterosubstituted Organozirconium Compounds. -Selective nucleophiles of low basicity. Preliminary communication
作者:Beat Weidmann、Christopher D. Maycock、Dieter Seebach
DOI:10.1002/hlca.19810640532
日期:1981.7.22
Solutions of the title compounds are accessible from organolithium reagents and trialkoxyzirconium chloride (equation 2). In contrast to their titanium analogues, vinylzirconium reagents are stable enough to be employed. Generally, organozirconium reagents are highly selective aldehyde and ketone carbonylophiles of exceedingly lowbasicity (Tables 1, 2, 3 and typical procedure).
Ketone Coupling with Alkyl Iodides, Bromides, and Chlorides Using Thulium Diiodide: A More Powerful Version of SmI<sub>2</sub>(THF)<i><sub>x</sub></i>/HMPA