developed for reactions of malonates with styrene derivatives. The concept of this process lies in the photo-oxidation of catalytic amounts of the enolate to form reactive radicals that react with alkene double bonds under mild reaction conditions. This is an example of visible-light-activated C–C bond formation reactions of malonates with alkenes to realize high atom economy under very mild reaction conditions
first reported use of benzeneperseleninic acid as a catalytic mediator for oxaziridinium ion catalysedepoxidation is described, providing reaction rates and ee values (up to 85%) similar to those reported when using oxone as the stoichiometric oxidant. A dual catalytic cycle is proposed, in which diphenyl diselenide is initially converted into the perseleninic acid, which in turn oxidises an iminium ion
首次报道了使用苯过硒酸作为 oxaziridinium 离子催化环氧化的催化介质,提供的反应速率和 ee 值(高达 85%)与使用 oxone 作为化学计量氧化剂时报道的相似。提出了双催化循环,其中二苯基二硒化物最初转化为过硒酸,后者又将亚胺离子氧化成相应的恶氮杂,从而促进不对称氧转移到烯烃。
Bromination of 1,1-diarylethylenes with bromoethane
bromides from the corresponding 1,1-diarylethylenes. This protocol not only provides a convenient and straightforward strategy for the rapid construction of various 2,2-diarylvinyl bromides without bromine and extra oxidants, but also can improve the atom economy of Kornblum oxidative reaction.
2,2 (Diarlyl) Vinylphosphine compound,
palladium catalyst thereof, and process for
producing arylamine, diaryl, or arylalkyne with
the catalyst
申请人:——
公开号:US20020058837A1
公开(公告)日:2002-05-16
A novel 2,2-(diaryl)vinylphosphine compound represented by the following general formula (1):
1
(wherein R
1
is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc.; R
2
, R
3
, R
4
, R
5
, R
6
, and R
7
may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc., provided that R
4
and R
5
taken together and/or R
6
and R
7
taken together may represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, etc.; and p, q, r, and s each is 0 to 5, provided that p+q and r+s each is in the range of from 0 to 5); a palladium-phosphine catalyst obtained by causing a palladium compound to act on the novel 2,2-(diaryl)vinylphosphine compound; and a process for obtaining an arylamine, a diaryl and an arylalkyne in the presence of the palladium-phosphine catalyst.
A general and direct electrochemicaldimethoxylation of olefins is reported, which enables a divergent route to different products depending on the structure of olefins. The present protocol features mild conditions and broad substrate scope (49 examples) obviating the usage of transtion‐metals and external oxidants. More importantly, to rationalize the divergent route of the transformation, an ionic‐like