Highly functionalized gamma-lactams are key intermediates for the synthesis of numerous biologically significant natural products. We herein described the synthesis of various chiral gamma-lactams via intramolecular C-H insertion of alpha-diazo-alpha-(phenylsulfonyl)acetamides derived from alpha-amino acids, which possess various functional groups. The cyclizations were highly regio- and stereoselective to afford chiral gamma-lactam motifs in high yields.
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