Preparation method for pyrrolidine-2-carboxylic acid derivatives
申请人:ZHEJIANG JIUZHOU PHARMACEUTICAL CO., LTD.
公开号:US20160145208A1
公开(公告)日:2016-05-26
The present invention relates to the field of medical synthesis, in particular to a preparation method for pyrrolidine-2-carboxylic acid derivatives. The present invention adopts the following technical solution: providing a compound having a structure of formula (E), wherein R is R
1
or R
2
, R
1
is C
1
-C
6
an alkyl, benzyl, p-methoxybenzyl, or p-nitrobenzyl group, and R
2
is hydrogen; R
3
is a protecting group of the carboxyl group; and P
1
is a protecting group on nitrogen.
Diastereoselective addition of organometallic reagents to chiral iminium ions: Synthesis of (S)-(+)-cryptostyline I.
作者:Richard P. Polniaszek、Lawrence W. Dillard
DOI:10.1016/s0040-4039(00)94630-6
日期:1990.1
participates in stereoselective nucleophilic addition reactions with Grignard reagents. Analysis of the products from reaction of 5-hexenylmagnesium bromide with iminium ion 2a suggests that these reactions proceed by a polar (two electron) mechanism. The utility of this chemistry is demonstrated in a stereospecific synthesis of (S)-(+)-cryptostylina I.
The invention provides compounds of formula (I) having nematicidal, insecticidal, acaricidal and fungicidal properties, compositions comprising them and processes and intermediates for their preparation: ##STR1## wherein: X is oxygen or sulphur; n is 0, 1 or 2; R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are as described in the specification.
Catalytic Parallel Kinetic Resolution under Homogeneous Conditions
作者:Trisha A. Duffey、James A. MacKay、Edwin Vedejs
DOI:10.1021/jo100695z
日期:2010.7.16
Two complementary chiral catalysts, the phosphine 8d and the DMAP-derived ent-23b, are used simultaneously to selectivelyactivate a mixture of two different achiral anhydrides as acyl donors under homogeneous conditions. The resulting activated intermediates 25 and 26 react with the racemic benzylic alcohol 5 to form enantioenriched esters (R)-24 and (S)-17 by fully catalyticparallelkinetic resolution
两种互补的手性催化剂,膦8d和 DMAP 衍生的ent - 23b,同时用于在均相条件下选择性活化作为酰基供体的两种不同非手性酸酐的混合物。所得活化中间体25和26与外消旋苯甲醇5反应,通过完全催化平行动力学拆分(PKR)形成对映体富集的酯( R ) -24和( S ) -17。对于 PKR 过程,芳酰基酯 ( R )- 24以近乎理想的对映选择性获得,但 ( S)- 17被大约污染。8% 的次要对映异构体 ( R ) -17来自第二个途径,通过形成混合酸酐27并在8d激活。
Synthesis of indoles via alkylidenation of acyl hydrazides
作者:Kevin Hisler、Aurélien G.J. Commeureuc、Sheng-ze Zhou、John A. Murphy
DOI:10.1016/j.tetlet.2009.02.060
日期:2009.7
synthesised via alkylidenation of acyl phenylhydrazides using phosphoranes and the Petasis reagent, followed by in situ thermal rearrangement of the product enehydrazines. The Petasis reagent provides an essentially neutral equivalent of the [acid-catalysed] Fischer indole synthesis, but with acyl phenylhydrazides as starting substrates. Alkylidene triphenylphosphoranes convert aroyl phenylhydrazides to indoles