Carbon kinetic isotope effects and transition structures in the rearrangements of allyl vinyl ethers. 2-(Trimethylsilyloxy)-and 2-(Methoxycarbonyl)-3-oxa-1, 5-hexadiene

L Kupczyk-Subotkowska, WH Saunders Jr…

Index: Kupczyk-Subotkowska, Lidia; Saunders Jr., William H.; Shine, Henry J.; Subotkowski, Witold Journal of the American Chemical Society, 1994 , vol. 116, # 16 p. 7088 - 7093

Full Text: HTML

Citation Number: 17

Abstract

Abstract: l4C KIE (kinetic isotope effects) were measured for the C-1, C-2, C-4, and C-6 positions in the rearrangement of 2-(trimethylsi1oxy)-(la) and 2-(methoxycarbonyl)-3-oxa-1, 5-hexadiene (lb). The data, along with earlier C-4 and C-6 deuterium KIE, were fitted to Bebovib modeling calculations. The calculations show that in the transition structure (TS) for la 70-80% bond breaking and 20% of bond making occurs, whereas in the TS of lb both ...