The combination of carbaboranylmercuric chloride (new type of bulky Lewis acid) and silver triflate efficiently catalyzes cycloisomerization of 1, 3-dienes at room temperature. The catalytic system gives allyl-substituted azacycles and cycloalkanes in excellent yields with high to complete regioselectivity.
Intramolecular Hydroamination/Cyclization of Conjugated Aminodienes Catalyzed by Organolanthanide Complexes. Scope, Diastereo- and Enantioselectivity, and Reaction Mechanism
作者:Sukwon Hong、Amber M. Kawaoka、Tobin J. Marks
DOI:10.1021/ja036266y
日期:2003.12.1
precatalysts for the rapid, regioselective, and highly diastereoselective intramolecularhydroamination/cyclization of primary and secondary amines tethered to conjugated dienes. The rates of aminodiene cyclizations are significantly more rapid than those of the corresponding aminoalkenes. This dienyl group rate enhancement as well as substituent group (R) effects on turnover frequencies is consistent with
Highly Stereoselective Intramolecular Hydroamination/Cyclization of Conjugated Aminodienes Catalyzed by Organolanthanides
作者:Sukwon Hong、Tobin J. Marks
DOI:10.1021/ja020226x
日期:2002.7.1
Efficient intramolecularhydroamination/cyclization of primary and secondary conjugated aminodienes can be effected by using organolanthanide precatalysts of the type Cp'2LnCH(TMS)2 (Cp' = eta5-Me5C5; Ln = La, Sm, Y; TMS = SiMe3) and CGCSmN(TMS)2 (CGC = Me2Si(eta5-Me4C5)(tBuN)). The transformation proceeds cleanly (>/= 90% conversion) at 25-60 degrees C with good rates and high regioselectivities,