A palladium-catalyzed stereospecific alkylation of allylamines with primary and secondaryalkyliodides is described. Isoquinoline-1-carboxamide (IQA) acts as directing group to generate multisubstituted olefin products in cis configuration in moderate to good yields. Mechanistic studies suggest that alkenyl C–H bond activation is the rate-determining step.
Synthesis and Activity of 6-Substituted Purine Linker Amino Acid Immunostimulants
作者:Boulos Zacharie、Lyne Gagnon、Giorgio Attardo、Timothy P. Connolly、Yves St-Denis、Christopher L. Penney
DOI:10.1021/jm960844m
日期:1997.8.1
Further, this potent in vitro activity was reflected as a significant increase in CTL cell number in vivo. However, immunophenotyping of some of the other equipotent compounds did not reveal a parallel relative increase in CTLs in vivo. It was difficult to formulate a rigorous structure-activity relationship based on in vitro CTL activity. Nevertheless, the activity was dependent upon the nature of
Sulfonamide-Promoted Palladium(II)-Catalyzed Alkylation of Unactivated Methylene C(sp<sup>3</sup>)H Bonds with Alkyl Iodides
作者:Kai Chen、Bing-Feng Shi
DOI:10.1002/anie.201407848
日期:2014.10.27
The alkylation of unactivated β‐methylene C(sp3)H bonds of α‐amino acid substrates with a broad range of alkyliodides using Pd(OAc)2 as the catalyst is described. The addition of NaOCN and 4‐Cl‐C6H4SO2NH2 was found to be crucial for the success of this transformation. The reaction is compatible with a diverse array of functional groups and proceeds with high diastereoselectivity. Furthermore, various
描述了使用Pd(OAc)2作为催化剂,将α-氨基酸底物的未活化β-亚甲基C(sp 3)H键与多种烷基碘进行烷基化。发现添加NaOCN和4-Cl-C 6 H 4 SO 2 NH 2对于该转化成功至关重要。该反应与各种各样的官能团相容,并且以非对映选择性高的方式进行。此外,通过顺序C(sp 3)制备了各种β,β-杂二烷基和β-烷基-β-芳基-α-氨基酸丙氨酸衍生底物的H功能化,从而为非天然β-二取代α-氨基酸的立体选择性合成提供了一种通用策略。
An Easy, General and Practical Method for the Construction of Alkyl Sulfonyl Fluorides
and 3° alkyl iodides to ethenesulfonyl fluoride, employing Hantzschester as a hydrogen source at room temperature was developed. This method featured a wide substrate scope and great functional group compatibility, providing facile and robust process to alkyl sulfonyl fluorides including enzyme inhibitors, natural products and drugs derivatives in up to 99% yield. Further derivatization of resultant
Pd(ii)-catalyzed alkylation of unactivated C(sp3)–H bonds: efficient synthesis of optically active unnatural α-amino acids
作者:Kai Chen、Fang Hu、Shuo-Qing Zhang、Bing-Feng Shi
DOI:10.1039/c3sc51747k
日期:——
A palladium-catalyzedalkylation of primary and secondary C(sp3)–H bonds with alkyl iodides and/or bromides for the synthesis of optically active unnatural α-amino acids (α-AAs) is described. This process is scalable and tolerates a variety of functional groups with complete retention of chirality, providing an efficient new strategy for the synthesis of various unnatural α-amino acid derivatives.