Branched α-amino acids incorporating an alkynyl group have been prepared by copper-catalysed reaction of a serine-derived organozinc reagent with bromoallenes. Substantial improvements to our previously reported Negishi cross-coupling of the serine-derived organozinc reagent with cycloalkenyl triflates are possible using a combination of LiCl and SPhos as ligand. Finally, we report a preliminary example