Kinetic isotope effects in the thermal C2-C6 cyclization of enyne-allenes: experimental evidence supports a stepwise mechanism.
Kinetic isotope effects suggest that the thermal C2-C6 cyclization of enyne-allenes proceeds through a stepwise diradical mechanism. This is even true if steric bulk at the alkyne terminus is large, contrary to theoretical predictions by Engels.
Schmittel
Michael
M
Organische Chemie I, FB 8, Universität Siegen, Adolf-Reichwein-Strasse, D-57068 Siegen, Germany. schmittel@chemie.uni-siegen.de
Vavilala
Chandrasekhar
C