Assessing the halogen effect in Diels–Alder reactions involving chiral a-haloenones. A combined experimental and DFT computational approach

SAROTTI, A.M.; SPANEVELLO, R.A.; SUÁREZ, A.G.

TETRAHEDRON LETTERS

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2011 vol. 52 p. 4145 - 4148

0040-4039

  An experimental and computational study was conducted to assess the effect of chlorine and bromine substitution in Diels–Alder reactions involving chiral a-halo enones as dienophiles. An important rate enhancement was observed in the case of acyclic dienes, while the use of cyclic dienes resulted in prolonged reaction times and lower yields. DFT calculations suggest that these reactions are governed by finely balanced geometric and electronic features at the TSs