. . " carbinol with a halogen substituted aromatic aldehyde of formula II: ##STR9## wherein the A--CHO substituent is ortho, meta, or para to X; X is either bromine or iodine; A is a single bond or a group with a continuous pi electron system conjugated to the aldehyde carbonyl; R3 is any non-interfering ring substituent; and n is 0, 1, 2, 3 or 4; to produce a protected ethynyl aromatic aldehyde of for" . .