Ring expansion of donor-acceptor cyclopropanes bearing arylcarbamoyl group into 1,5-diarylpyrrolidin-2-ones

The rearrangement of 2,N-diaryl-1-carbamoylcyclopropanecarboxylates upon their treatment with titanium(iv) chloride was found to proceed as ring expansion affording 1,5-diaryl-2-oxopyrrolidine-3-carboxylates. In the resulting products, the ester group can be easily removed via either the Krapcho reaction or alkaline hydrolysis followed by the thermal decarboxylation.

Automated summary

The rearrangement of 2,N-diaryl-1-carbamoylcyclopropanecarboxylates upon treatment with titanium(iv) chloride results in ring expansion and the formation of 1,5-diaryl-2-oxopyrrolidine-3-carboxylates. The ester group in the resulting products can be easily removed through either the Krapcho reaction or alkaline hydrolysis followed by thermal decarboxylation.