magnesium; zinc dibromide in diethyl ether T=0°C; 2.5 h; Further stages. Title compound not separated from byproducts.;

1: 3-bromo-1-(trimethylsilyl)-1-propyne With aluminium; PbCl2 in tetrahydrofuran T=0°C; 1 h; Inert atmosphere; 2: cyclohexanone in tetrahydrofuran T=0°C; Inert atmosphere;

in tetrahydrofuran T=0°C; 1 h;

Yield given. Multistep reaction;