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,
no)methyl]pyridine. It was used in the asymmetricintramolecularhydroamination of amino-1,3-dienes, with the desired products being obtained in good yields and with excellent regioselectivities and up to moderate enantioselectivities. The absolute configuration of one of the hydroamination products was determined by X-ray crystallography studies. This simple and efficient procedure can be used for
Simple and easily accessible chiral lithium amide salts are reported as efficient (pre)catalysts for the diastereo‐ [up to (E:Z)=92:8] and enantioselective [up to 72% ee (E)] hydroamination/cyclisation of conjugated primary aminodienes. These chiral lithium salts are straightforwardly prepared by in situ combination of an N‐substituted (R)‐(+)‐1,1′‐binaphthyl‐2,2′‐diamine ligand and a commercial methyllithium
The aqueous Diels-Alderreactions of a series of dienyl ammonium chlorides derived from (E)-2,4-pentadienylamine, (E)-3,5-hexadienyl amine and (E)-4,6-heptadienyl amine with a variety of dienophiles have been examined. A similar Diels-Alder study employing the sodium salt of N-(E)-4,6-heptadienyl succinamic acid in water was also undertaken.
Regio- and Enantioselective Hydroamination of Dienes by Gold(I)/Menthol Cooperative Catalysis
作者:Osamu Kanno、Wataru Kuriyama、Z. Jane Wang、F. Dean Toste
DOI:10.1002/anie.201104076
日期:2011.10.10
Alcohol is key: Regio‐ and enantioselectivehydroamination of 1,3‐dienes has been achieved with the dinuclear catalyst (R)‐DTBM‐SEGPHOS. The rate and selectivity of the reaction are enhanced by alcohol additives like menthol, which coordinates the cationic gold(I) to generate a Brønsted acid that can participate in catalysis. Mbs=p‐methoxybenzenesulfonyl.
醇是关键:已使用双核催化剂 ( R )-DTBM-SEGPHOS实现了 1,3-二烯的区域选择性和对映选择性加氢胺化。醇类添加剂如薄荷醇可提高反应的速率和选择性,薄荷醇与阳离子金 (I) 配位以生成可参与催化的布朗斯台德酸。Mbs=对甲氧基苯磺酰基。