Download PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... Benzylic halides coupled with 1-alkynylmagnesium halides in the presence of a catalytic amount of Co(acac) 3 to provide 1-aryl-2-alkynes in moderate to good yield. ... Benzylic halides coupled with 1-alkynyl Grignard reagents in the presence of Co catalyst. ... First, we surveyed the ...