Palladium(II) catalyzed cyclization of alkynoic acids
作者:Claude Lambert、Kiitiro Utimoto、Hitosi Nozaki
DOI:10.1016/s0040-4039(01)81594-x
日期:——
Under the catalytic action of palladium(II) in the presence of triethylamine, 3-, 4-, and 5-alkynoic acids afford 3-buten-4-olides, 4-penten-4-olides, and 5-hexen-5-olide, respectively, in good to excellent yields.
A novel visible light mediated cyclization of enol lactones with difluoroacyl arenes via a free radical tandem difluoroalkylation and C–C coupling of butenolides is presented. This strategy provides a facile approach to potential biological fluorinated γ-butyrolactones with excellent diastereoselectivity.
Rhodium-Catalyzed Highly Enantio- and Diastereoselective Alkenylation of β,γ-Unsaturated Butenolides via Dynamic Kinetic Resolution
作者:Xiaosa Lu、Jie Zhu、Yinhua Huang
DOI:10.1021/acs.orglett.2c03551
日期:2022.12.9
diene ligand, (S,S)-Ph-bod, enables the facile synthesis of chiral butyrolactones in high yields with extremely high enantioselectivities (>99% ee in all cases) and high diastereoselectivities (up to >20:1 dr). The key process of the reaction involves the isomerization of β,γ-unsaturated butenolides to racemic α,β-unsaturated butenolides and the subsequent dynamic kinetic resolution through ligand-controlled
报道了一种铑催化的 β,γ-不饱和丁烯酸内酯的高度对映和非对映选择性烯基化反应。使用手性二烯配体 ( S , S )-Ph-bod,能够以高产率轻松合成手性丁内酯,具有极高的对映选择性(在所有情况下 >99% ee)和高非对映选择性(高达 >20: 1 博士)。反应的关键过程包括 β,γ-不饱和丁烯酸内酯异构化为外消旋 α,β-不饱和丁烯酸内酯,以及随后通过配体控制的动态动力学拆分,通过 1,4 原位生成的烯基铑物质进行对映选择性烯基化- 铑迁移。
Verwendung von Oxyacetaldehyden als Maiglöckchen-Riechstoffe
申请人:Symrise AG
公开号:EP2594626A1
公开(公告)日:2013-05-22
Beschrieben wird die Verwendung bestimmter Verbindungen aus der Gruppe der Oxyacetaldehyde als Riechstoffe mit einer Maiglöckchen-Note, und/oder als Mittel zum Erhöben der Substantivität und/oder der Retention einer Riechstoffzubereitung und/oder als Fixateur.
A solid, free-flowing composition adapted to deliver fragrance or malodor counteractant in a consumer product that is subjected to actual or potential malodorous influences, comprising:
a delivery system consisting of a core material surrounded by a fragranced material comprising microdroplets of a dispersed fragrance in a fragrance-encapsulating material, optionally surrounded by a protective coating,
and,
an external absorbent material in which the fragrance delivery vehicle is dispersed.
The invention is especially effective with respect to animal litters, especially those for cats.