One, two, three, four: A copper(I)–phosphine complex catalyzes the diborylation of alkynes and arynes, and the tri‐ or tetraborylation of propargyl ethers (see scheme; pin=pinacolato). In the latter cases, the CO bond(s) as well as the CC bond are borylated in one pot. Furthermore, a diborylation product serves as an intermediate in the efficient synthesis of ortho‐terphenyls with pharmacological
Highly Stereoselective Semihydrogenation of Alkynes Promoted by Nickel(0) Nanoparticles
作者:Francisco Alonso、Iñaki Osante、Miguel Yus
DOI:10.1002/adsc.200505327
日期:2006.2
A new method for the highlystereoselective cis-semihydrogenation of internal alkynes is described based on in situ generated Ni(0) nanoparticles and molecular hydrogen. This reduction system also allows the semihydrogenation of terminal alkynes.
Treatment of homopropargylic alcohol derivatives or phenylacetylene compounds with phenylmagnesium bromide in the presence of a catalytic amount of manganese(II) chloride afforded phenylated products in good yields with high regio- and stereoselectivities.
在催化量的氯化锰 (II) 存在下,用溴化苯基镁处理高炔丙醇衍生物或苯乙炔化合物,以高产率和高区域选择性和立体选择性提供苯化产物。
Allylmanganation and diallylation of acetylenic compounds
stereoselectivities. The intermediary alkenylmanganese compounds were trapped by various electrophiles. The reaction was clearly oxygen-assisted since 6-dodecyne was completely recovered unchanged. Diallylation products were obtained in the presence of air. Allylmagnesation and diallylation of these acetyleniccompoundscatalyzed by manganesesalts are also disclosed.
The cobalt-catalyzed allylzincation reaction of 1-phenyl-1-alkynes proceeds with high regio- and stereoselectivity. The resultant alkenylzinc species undergo further functionalization upon treatment with electrophiles.