作者:Qing-Gang Tang、Sen-Lin Cai、Chuan-Chuan Wang、Guo-Qiang Lin、Xing-Wen Sun
DOI:10.1021/acs.orglett.0c00779
日期:2020.5.1
A simple, direct, and highly enantioselective synthesis of spiro-oxindole piperidin-2-one derivatives was achieved through an aza-Michael/Michael cyclizationcascade sequence using a squaramide catalyst. The desired products were obtained in excellent yields (up to 99%) and good to high stereoselectivities (up to >20:1 dr and up to 99% ee) under mild conditions.
使用方酰胺催化剂通过氮杂迈克尔/迈克尔环化级联序列实现了螺-羟吲哚哌啶-2-酮衍生物的简单、直接和高度对映选择性合成。在温和条件下以优异的收率(高达 99%)和良好的立体选择性(高达 >20:1 dr 和高达 99% ee)获得所需的产物。
Electrocoat materials comprising bismuth compounds, further comprising (A) at least one self-crosslinking and/or externally crosslinking binder containing (potentially) cationic or anionic groups and reactive functional groups which (i) with themselves or with complementary reactive functional groups in the self-crosslinking binder, or (ii) in the case of the externally crosslinking binder, with complementary reactive functional groups present in crosslinking agents (B) are able to undergo thermal crosslinking reactions, (B) if desired, at least one crosslinking agent comprising the complementary reactive functional groups, and
(C) bismuth subsalicylate of empirical formula C
7
H
5
O
4
Bi.
NITROGEN-CONTAINING HETEROCYCLIC COMPOUNDS AND METHODS OF MAKING THE SAME
申请人:Jeffrey Christopher S.
公开号:US20120271046A1
公开(公告)日:2012-10-25
The present invention relates to 7-membered nitrogen-containing heterocyclic compounds and methods of making the same. Using a novel aza-[4+3] cycloaddition reaction, the 7-membered heterocyclic compounds are synthesized by reacting a first reactant and a second reactant. Exemplary first reactants and second reactants include α-halohydroxamates and dienes, respectively.
Samariumdiiodide is an efficient catalyst for the aza-Michael addition of O-benzylhydroxylamine to α,β-unsaturated N-acyloxazolidinones leading to mixtures of the Michael adduct and the product resulting from its amidation. Samarium iodobinaphtholate catalyzed reactions selectively afford the Michael adducts with enantiomeric excesses up to 88 %. An isoinversion effect with temperature is observed
二碘化钐是一种有效的催化剂,用于将 O-苄基羟胺与 α,β-不饱和 N-酰基恶唑烷酮进行氮杂-迈克尔加成,从而形成迈克尔加合物及其酰胺化产物的混合物。碘联萘酸钐催化的反应选择性地提供对映体过量高达 88% 的迈克尔加合物。在 -40 °C 时观察到对映体过量最高的温度的同位倒置效应。
Facile Synthesis of Functionalized 1,4‐Benzodiazepine‐3‐One‐5‐Acetates via [4 + 3]‐Annulation of Azaoxyallyl Cations With 2‐Aminophenyl α,β‐Unsaturated Esters
作者:Hyun Sun Jang、Yong Il Kwon、Sung‐Gon Kim
DOI:10.1002/bkcs.12060
日期:2020.7
metal‐free [4 + 3]‐annulation of α‐halohydroxamates with 2‐aminophenyl α,β‐unsaturated esters has been developed for the construction of seven‐membered 1,4‐benzodiazepine‐3‐one‐5‐acetates in moderate to good yields (up to 82% yield). The annulation involved the cascade reaction of an generation of azaoxyallyl cation, aza‐addition to this azaoxyallyl cation, and intramolecular aza‐Michael reaction to yield 1