In the presence of phosphine catalyst and pinacolborane, ynones undergo 1,2-reduction while ynoates undergotrans-hydroboration. Mechanistic insights into the two competing pathways lay grounds for control of selectivity in these processes.
Gold-catalyzed Fluorination of Alkynyl Esters and Ketones: Efficient Access to Fluorinated 1,3-Dicarbonyl Compounds
作者:Xiaojun Zeng、Zhichao Lu、Shiwen Liu、Gerald B. Hammond、Bo Xu
DOI:10.1002/adsc.201701179
日期:2017.11.23
We developed an efficient synthesis of 2-fluoro-1,3-dicarbonyl compounds using readily available alkynyl ketones or esters as starting material. The key step is the insertion of hydrogen fluoride (HF) to the gold carbene intermediate generated from cationic gold catalyzed addition of N-oxides to alkynyl ketones or esters. This method gives excellent chemical yields and regioselectivity with good functional
Pyridine and pyrimidine derivatives as mGIuR2 antagonists
申请人:McArthur Silvia Gatti
公开号:US20070232583A1
公开(公告)日:2007-10-04
The present invention relates to compounds of formula (I), a process for the manufacture thereof, pharmaceutical compositions containing them, and their use for treating CNS disorders:
wherein A, B, X, Y, R
1
, R
2
, R
3
and R
4
are as defined in the description and claims.
A phosphane‐catalyzed [3+3] annulation of azomethineimines with ynones has been developed. Under mild reaction conditions, the reaction proceeds smoothly to afford tricyclic dinitrogen‐fused heterocyclic compounds in moderate to excellent yields with moderate to excellent stereoselectivies. Using a chiral phosphine as the catalyst, the reaction could work to give the cycloadduct in moderate yield
Lewis-base-catalysed selective reductions of ynones with a mild hydride donor
作者:F. Schömberg、Y. Zi、I. Vilotijevic
DOI:10.1039/c8cc00058a
日期:——
Ynones are efficiently reduced with a mild hydride donor in the presence of a catalytic amount of nucleophilic phosphines. The reactions are selective 1,2-reductions that give propargyl alcohols in yields of up to 96%. It is proposed that success in these reactions depends on the activation of ynones by a Lewis base catalyst. A protic additive plays a key role in suppressing the undesired reaction