Ma Shengming, Zhang Junliang, Lu Lianghua
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, P. R. China.
Chemistry. 2003 Jun 6;9(11):2447-56. doi: 10.1002/chem.200204664.
Described herein is the Pd(0)-catalyzed coupling cyclization reaction of 1,2-allenyl ketones with organic halides leading efficiently and conveniently to not only 2,3,4- and 2,3,5-trisubstituted furans but also 2,3,4,5-tetrasubstituted furans. Furthermore, this method showed high substituent-loading capability and tolerance of various substituents. The reactions of 1,2-allenyl ketones 1 e, 1 p, 1 q, and deuterated [D]1 c were performed for a mechanistic study, which demonstrated that instead of an enolization pathway, the reaction may proceed via the intermediacy of dienolate palladium and intramolecular nucleophilic attack on the pi-allyl palladium intermediate by the carbonyl oxygen.
本文描述了钯(0)催化的1,2-联烯基酮与有机卤化物的偶联环化反应，该反应不仅能高效便捷地生成2,3,4-和2,3,5-三取代呋喃，还能生成2,3,4,5-四取代呋喃。此外，该方法显示出高取代基负载能力和对各种取代基的耐受性。对1,2-联烯基酮1 e、1 p、1 q和氘代的[D]1 c进行了反应以进行机理研究，结果表明该反应可能不是通过烯醇化途径，而是通过烯醇钯酸酯中间体，并由羰基氧对π-烯丙基钯中间体进行分子内亲核进攻来进行。
