Upon treatment with a palladium catalyst, (o-iodoanilinoalkyl)allene compounds undergo intramolecular carbopalladation of allenes followed by intramolecular amination of Ï-allylpalladium complexes to afford indole derivatives in fairly good yields.
Hydroalkoxylation Catalyzed by a Gold(I) Complex Encapsulated in a Supramolecular Host
作者:Z. Jane Wang、Casey J. Brown、Robert G. Bergman、Kenneth N. Raymond、F. Dean Toste
DOI:10.1021/ja202055v
日期:2011.5.18
Gold(I)-phosphine complexes are readily encapsulated by a tetrahedral supramolecular host (Ga(4)L(6)). We have investigated the catalytic activity of the resulting complexes for the intramolecular hydroalkoxylation of allenes. The catalytic activity of Me(3)PAuBr was increased 8-fold by encapsulation, as determined by initial rate kinetics, and we observed up to 67 catalytic turnovers by Me(3)PAu(+)
Allene Epoxidation. Highly functionalized tetrahydrofurans and tetrahydropyrans from the oxidative cyclization of allenic alcohols.
作者:Jack K. Crandall、David J. Batal、Feng Lin、Thierry Reix、Gregory S. Nadol、Raymond A. Ng
DOI:10.1016/s0040-4020(01)92232-x
日期:1992.2
The dimethyldioxirane oxidation of various allenic alcohols yields highlyfunctionalizedtetrahydrofuran and tetrahydropyran derivatives via intramolecular nucleophilic addition of the hydroxy group to an intermediate allene diepoxide.
Intramolecular Palladium(II)-Catalyzed 1,2-Addition to Allenes
作者:Catrin Jonasson、Attila Horváth、Jan-E. Bäckvall
DOI:10.1021/ja001748k
日期:2000.10.1
were performed in the presence of LiBr with Pd(OAc)2 as the catalyst. Two different reoxidants, p-benzoquinone or Cu(OAc)2, were used, the choice of oxidant being dependent on the substrate. The reaction proceeds through an external nucleophilic attack (Br-) on a (π-allene)palladium complex to produce a (π-allyl)palladium intermediate. Subsequent intramolecular attack by the second internal nucleophile
钯 (II) 催化分子内 1,2-加成到被内部亲核试剂取代的丙二烯。羧酸、醇、N-取代酰胺和氨基甲酸酯用作钯催化反应中的内部亲核试剂,以良好的分离产率提供内酯、四氢吡喃、四氢呋喃、吡咯烷和恶唑烷酮。该反应在 LiBr 存在下以 Pd(OAc)2 作为催化剂进行。使用了两种不同的再氧化剂,对苯醌或 Cu(OAc)2,氧化剂的选择取决于底物。该反应通过对(π-丙二烯)钯络合物的外部亲核攻击(Br-)进行,以产生(π-烯丙基)钯中间体。随后第二个内部亲核试剂的分子内攻击产生产物。中间体(π-烯丙基)钯配合物被分离和表征。研究了反应的范围和局限性及其机理和选择性,在不同的反应...
Gold(I)-Catalyzed Enantioselective Synthesis of Pyrazolidines, Isoxazolidines, and Tetrahydrooxazines
作者:R. L. LaLonde、Z. J. Wang、M. Mba、A. D. Lackner、F. Dean Toste
DOI:10.1002/anie.200905000
日期:2010.1.12
Au‐ff on a trip: Chiral ligands (L*) and chiral anions [(S)‐TriPAg] are employed in the gold(I)‐catalyzedenantioselectiveintramolecular additions of hydrazines and hydroxylamines to allenes. These complementary methods allow access to chiral vinyl isoxazolidines, oxazines, and differentially protected pyrazolidines. PNB=para‐nitrobenzoyl.