A metal-free intramolecular borylative cyclization of 1,6-allenynes driven by BCl 3 was developed. This method provides a general and practical strategy to construct valuable pyrrolidines containing all-carbon quaternary centers or 3,5dihydroazepine derivatives depending on the substituents of the allene, with conjugative and sterically hindered phenyl groups favoring the latter.

A direct and convenient approach for the coupling of propargylic substrates with diphenylphosphine oxide in the presence of Tf 2 O and 2,6-lutidine has been developed. The method provides a general approach for the construction of attractive allenylphosphoryl skeletons with high atom and step economy under metal free conditions.