This document discusses the Shapiro reaction, which was discovered by Robert H. Shapiro in 1967. The reaction involves converting aryl sulfonyl hydrazones of aldehydes and ketones into olefins using alkyl lithium reagents, grignard reagents, or alkali metal amides at -78属C. The reaction mechanism proceeds through deprotonation, elimination, and loss of nitrogen to form alkenyl intermediates. The Shapiro reaction has been used in the total synthesis of natural products like phytocassane D and in the formation of ring B in the Nicolaou Taxol total synthesis.