One-Pot Synthesis of 1-(1-Alkoxyethoxy)allenes

A convenient one-pot procedure has been proposed for the preparation of 1-(1-alkoxyethoxy)allenes from alkoxyethenes and prop-2-yn-1-ol with the use of trifluoroacetic acid as highly efficient catalyst for the synthesis of 3-(1-alkoxyethoxy)prop-1-ynes and of the system t-BuOK–DMSO for the isomerization of the latter into allenes.