[Wisemanleo]

Alright, so I've followed Taylor's prep on diphenyl ketene synthesis (Org. Syn., Coll. Vol 6, p.549 (1988); Vol. 52, p.36 (1972)).

I've had success up to the point where I have to remove the ether under reduced pressure and then distill the residual red oil. I removed the ether via rotavap to reveal a lime-green granular residue, and then I distilled it using a special small-scale distilling apparatus. By the end of it, a red-blackish residue remained (supposed to be an orange oil). I immediately froze this compound. I ran an IR and I didn't see the characteristic ketene peak at 2100cm-1. So obviously, I screwed up somewhere. I'm thinking I maybe pulled off the diphenyl ketene right through the rotavap....

Any tips?