56075-22-0Relevant academic research and scientific papers
A Nickel-catalyzed carbozincation of aryl-substituted alkynes
Stuedemann, Thomas,Ibrahim-Ouali, Malika,Knochel, Paul
, p. 1299 - 1316 (1998)
The addition of dialkylzincs or diphenylzinc to substituted phenylacetylenes in the presence of catalytic amounts of Ni(acac)2 in THF:NMP mixtures produces syn-carbozincation products with good to excellent regio- and stereoselectivity. After quenching with an electrophile (iodine, acyl chloride, allyl bromide) tetrasubstituted olefines are obtained in good to satisfactory yields. An intramolecular version of the reaction is possible using a terminal triple bond bearing an iodine at a remote position. More substituted iodo-alkynes furnish only reductive elimination products. An application to a stereoselective synthesis of (Z)-tamoxifen (Z:E > 99:1) has been developed.
New nickel-catalyzed carbozincation of alkynes: A short synthesis of (Z)-tamoxifen
Studemann,Knochel
, p. 93 - 95 (2007/10/03)
A new highlight in the repertoire of carbometalation reactions is the highly stereo- and regioselective nickel-catalyzed carbozincation of internal alkynes. This is exemplified by a short and effective synthesis of the anti-breast-cancer drug (Z)-tamoxifen. This reaction also allows the stereoselective synthesis of various tri- and tetrasubstituted olefins in good yield.
