Kinetics and mechanism of intramolecular Cyelization of (R)-undeca-7,8-dien-2-yne "a OFT study

A theoretical study of the kinetic and mechanism of intramoleccha cychcation of (1)-undeca-7,8-dien-2-yne was performed using MT methods at B3LYP and B3PW91 levels of theory using 6-311g, 6-311C.6-31 IGs*, 6-31I+G, 6-31 I4-SG and 6-3114H-Gs* basis seo. Equilibrium molecular geometries andharmonic vibrational frequencies of the reaccint, transition state and product wens calculated. Theconsidered rate constants and activation thermodynamic parameters were eak saluted. It wa.s demonstratedthat the obtained results for all calculations were nearly independent to basis sets at 83 PW91 I e el.These calculations showed that the reaction proceeds through asynchronous concerted mechanism,