The photochemical [2+2] cycloaddition of acetylene to chiral 2(5H)-furanones is investigated. The effect of the substituent at the stereogenic center of the lactone on the chemical yield and facial diastereoselectivity is evaluated. Using a C2-symmetric bis-lactone as substrate, a diastereomeric excess higher than 98% is found. © 2001 Elsevier Science Ltd. All rights reserved.
- Photochemical cycloadditions