Expedient Synthesis of 1,3-Cyclobutanedione via Thermal Dimerization of t-Butoxyethyne

Article abstract of DOI:10.1055/s-1985-31444

A new, short, and efficient synthesis of 1,3-cyclobutandione consists of the thermal conversion of 1-butoxyethyne into 3-t-butoxycyclobutenone (the first example of cyclobutenone formation from an unsubstituted acetylenic monoether) followed by cleavage of the t-butyl group with trifluoroacetic acid.The 62percent overall yield is much higher than that of the previously described procedure.