Abstract Metallation of allenyl thioethers, R 1 CH [DOUBLE BOND] C [DOUBLE BOND] CHSC 2 H 5 (I)(R 1= alkyl), by means of methyl-or butyl-lithium in ether, followed by addition of aldehydes or ketones, R 2 R 3 C [DOUBLE BOND] O (R 2 and R 3 are H or alkyl), affords a mixture of the two carbinols R 1 CH [DOUBLE BOND] C [DOUBLE BOND] C [[BOND] CR 2 R 3 C (OH)](SC 2 H 5)(III) and R 1 CH [[BOND] CR 2 R 3 (OH)] C [TRIPLE BOND] CSC 2 H ...