The reaction between acyl halides and alcohols: Alkyl halide vs. Ester formation
作者:Paolo Strazzolini、Angelo G. Giumanini、Giancarlo Verardo
DOI:10.1016/s0040-4020(01)80747-x
日期:1994.4
therefore, ester formation practically confined to a triggering role. But, in those cases where the cation is less easily formed, ester formation was favoured and, consequently, became the necessary elementary step towards alkylhalideformation. This final product, on the other hand, might be extremely slow to form in an SN2 reaction between the protonated ester function and the halideion. In these hnstances
The Mechanism of Oxidation of Allylic Alcohols to α,β-Unsaturated Ketones by Cytochrome P450
作者:Giuseppe Bellucci、Cinzia Chiappe、Laura Pucci、Pier Giovanni Gervasi
DOI:10.1021/tx9600053
日期:1996.1.1
The oxidation of cyclohex-2-en-1-ol, a simple model substrate for allylic alcohols, is catalyzed by several P450 isoenzymes and leads exclusively to cyclohex-2-en-1-one. No double bond epoxidation or C(4) hydroxylation have been observed. The large primary kinetic isotope effect measured using [2H]-1-cyclohex-2-en-1-ol is consistent with an at least partially rate limiting breaking of the C(1)-H bond
the palladium(II)-catalyzed Wacker-type cyclization of stereospecifically deuterated 6-(2-hydroxyphenyl)-3-deuteriocyclohexenes, cis-3-d-1 and trans-3-d-1, giving dihydrobenzofuran derivatives. The stereochemistry was determined to be syn in the reaction catalyzed by a dicationic palladium(II) catalyst generated from Pd(MeCN)4(BF4)2 and (S,S)-ip-boxax in the presence of benzoquinone in methanol, while
在钯 (II) 催化的瓦克型立体定向氘化 6-(2-羟基苯基)-3-氘代环己烯、cis-3-d-1 和反式环化反应中研究了氧化钯化步骤的立体化学途径(syn 或 anti) -3-d-1,得到二氢苯并呋喃衍生物。在苯醌的甲醇存在下,由 Pd(MeCN)4(BF4)2 和 (S,S)-ip-boxax 生成的双阳离子钯 (II) 催化剂催化的反应确定立体化学是同步的,而它在氯离子存在下由 PdCl2(MeCN)2 催化的反应中主要是反的。
Retention of Regiochemistry of Allylic Esters in Palladium-Catalyzed Allylic Alkylation in the Presence of a MOP Ligand
作者:Tamio Hayashi、Motoi Kawatsura、Yasuhiro Uozumi
DOI:10.1021/ja973150r
日期:1998.3.1
In the palladium-catalyzedallylicalkylation of (E)-3-substituted-2-propenyl acetates (1), 1-substituted-2-propenyl acetates (2), and 1- or 3-deuterio-2-cyclohexenyl acetate (5), which proceeds through 1,3-unsymmetrically substituted π-allylpalladium intermediates, selective substitution at the position originally substituted with acetate was observed by use of a sterically bulky monodentate phosphine
Cu(I)-Catalyzed, α-Selective, Allylic Alkylation Reactions between Phosphorothioate Esters and Organomagnesium Reagents
作者:Andrew M. Lauer、Farzeen Mahmud、Jimmy Wu
DOI:10.1021/ja202954b
日期:2011.6.15
of allylic alkylation reactions involving hard nucleophiles remains a significant challenge and continues to be an active area of research. The lack of general methods in which α-alkylation is favored underscores the need for the development of new processes for achieving this type of selectivity. We report that Cu(I) catalyzes the allylic substitution of phosphorothioate esters with excellent α-regioselectivity