Rhodium-Catalyzed Intermolecular Chelation Controlled Alkene and Alkyne Hydroacylation: Synthetic Scope of β-<i>S</i>-Substituted Aldehyde Substrates
作者:Michael C. Willis、Helen E. Randell-Sly、Robert L. Woodward、Steven J. McNally、Gordon S. Currie
DOI:10.1021/jo060582o
日期:2006.7.1
The use of β-S-substituted aldehydes in rhodium-catalyzed intermolecularhydroacylation reactions is reported. Aldehydes substituted with either sulfide or thioacetal groups undergo efficient hydroacylation with a variety of electron-poor alkenes, such as enoates, in Stetter-like processes and with both electron-poor and neutral alkynes. In general, the reactions with electron-poor alkenes demonstrate
Rhodium-Catalyzed Reductive Aldol Reactions Using Aldehydes as the Stoichiometric Reductants
作者:Michael C. Willis、Robert L. Woodward
DOI:10.1021/ja056130v
日期:2005.12.1
the addition of [Rh(dppe)]ClO4 to beta-sulfide-substituted aldehydes, can function as the stoichiometricreductants in reductive aldol processes. Unsaturated nitriles, esters, and ketones can be used as enolate equivalents, and a variety of simple alpha- and beta-substituted aldehydes can be employed. The use of a second, more electrophilic, aldehyde allows three-component reactions to be performed
Rhodium-Catalyzed Branched-Selective Alkyne Hydroacylation: A Ligand-Controlled Regioselectivity Switch
作者:Carlos González-Rodríguez、Rebekah J. Pawley、Adrian B. Chaplin、Amber L. Thompson、Andrew S. Weller、Michael C. Willis
DOI:10.1002/anie.201100956
日期:2011.5.23
It's all in the ligand: By choice of the appropriate diphosphine ligand a previously linear‐selective alkynehydroacylation process can be “switched” to be highly branched‐selective (see scheme, l=linear, b=branched). Structural data for the ortho‐iPr‐dppe–rhodium catalyst suggest restricted rotation of the phosphine aryl units may be responsible for the observed selectivity.
Carbazole derivatives and their use as neuropeptide y5 receptor ligands
申请人:——
公开号:US20040067999A1
公开(公告)日:2004-04-08
Compounds of formula (I): are described wherein R
1
-R
6
and m are as defined within. Processes for their preparation and their use as NPY 5 inhibitors is described.
The present invention relates to a process for preparing a compound of formula (Ia), (Ib), (Ic) or (Id), or a pharmaceutically acceptable salt, hydrate, solvate, complex or prodrug thereof, said process comprising the steps of: (A) (i) treating a compound of formula (IVa), where R
48
is alkyl or tosyl, with an oxidising agent to form a compound of formula (Va); and (ii) converting said compound of formula (Va) to a compound of formula (Ia) or (Ic); or (B) (i) treating a compound of formula (IVb), where R
48
is alkyl or tosyl, with an oxidising agent to form a compound of formula (Vb); and (ii) converting said compound of formula (Vb) to a compound of formula (Ib) or (Id).