Enyne computational study

Synopsis of Ochiai, Tomita, and Endo (2001) Investigation on Radical Polymerization Behavior of 4-Substituted Aromatic Enynes. Experimental, ESR, and Computational Studies . 

PraU, M. Wittkopp, A. Schreiner, P. R. Can fulvenes form from enediynes A systematic high-level computational study on parent and benzannelated enediyne and enyne—allene cyclizations, 7. Phys. Chem. A 2001,105, 9265-9274. 

Htibner, H. Haubmann, C. Utz, W. Gmeiner, P. (2000) Conjugated enynes as nonaromatic catechol bioisosteres synthesis, binding experiments, and computational studies of novel dopamine receptor agonists recognizing preferentially the D3 subtype. J. Med. Chem. 43, 756-762. 

A computational study of ring-closing enyne metathesis of l-allyloxy-2-propyne with the Grubbs-Hoveyda complex has revealed that ene-then-yne and yne-then-ene pathways proceed through equivalent steps, the difference being the order in which they take place there is no clear energetic preference for either. 

A computational study of the gold(I)-catalysed alkenylsilylation reaction of a silyl-tethered 1,6-enyne system has been shown to involve bistriflimide counterion-assisted rearrangements of carbocation and silyl cation intermediates (Scheme 132). ... 

Cope and Sila-Cope Rearrangements Computational studies by Yates et ed. on 1,5-enynes were used to rationalize the different regioselectivities observed for the Au(I)-catalyzed addition of alcohols to the all carbon (X = C) and silyl 1,5-enynes (X = Si) as shown in Eq. (5.9) [35]. 

Schreiner, P.R., Navarro-Vazques, A. and Prall, M. (2005) Computational studies on the cyclizations of enediynes, enyne-allenes, and related polyunsaturated systems. Accounts of Chemical Research, 38(1), 19-i7. 

A theoretical investigation of the thermal rearrangements of l-hexen-5-yne, 1,2,5-hexatriene, and 2-methylenebicyclo[2.1.0]pentane has been reported providing a theoretical account of the pyrolysis reactions. The computed energy values are in agreement with experimental product distributions. The thermal C(2)-C(6)/ene cyclization of enyne-allenes has been reviewed. A computation study of the thermal rearrangements of l-ethynyl-2-methylcyclopropane has been reported. " ... 

Singleton carried out a combined experimental/computational/MD study of the enyne-allene cyclization problem. First, he determined that the experimental KIE for the cyclization of 60 is 1.43. This value is smaller than that usually found for concerted ene reactions, where kg/kjj is often greater than... 

Computer modeling of thermal C -C cyclization of enyne-carbodiimide 3.968b (Scheme 3.146, A = B = N) [424] showed that intermediate 3.970b (for A = B = N) to be a diradical, as for (A = B = C) [424]. However, subsequent kinetic study of the process including the influence of solvent and the nature of substitution showed that the intermediate 3.970b is either carbene (for the case of electron-withdrawing substituents) or a zwitterion (for electron-releasing substituents). 

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