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DFT Studies on the Stereoselectivity of ?-Silyloxy Diazoalkane Cycloadditions.

ABSTRACT: The intramolecular [3+2] cycloaddition (32CA) of alkene-tethered ?-silyloxydiazoalkanes provides variable stereoselectivity in generating bicyclic pyrazolines where the silyloxy group is either syn or anti to the newly formed pyrazoline ring. To elucidate the origin of the stereoselectivity, density functional theory (DFT) calculations were carried out for the energy of each transition state structure (TSs) and product. Steric effects were identified as the major determining factors in the diastereoselectivity of the 32CA reaction with regards to substrate structure (cyclic or acyclic ?-silyloxydiazoalkanes).

SUBMITTER: O'Connor MJ

PROVIDER: S-EPMC6331888 | biostudies-other | 2015 Dec

REPOSITORIES: biostudies-other

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DFT Studies on the Stereoselectivity of α-Silyloxy Diazoalkane Cycloadditions.

O'Connor Matthew J MJ Liu Huaqing H Lee Daesung D Zhou Tao T Xia Yuanzhi Y

Molecules (Basel, Switzerland) 20151202 12

The intramolecular [3+2] cycloaddition (32CA) of alkene-tethered α-silyloxydiazoalkanes provides variable stereoselectivity in generating bicyclic pyrazolines where the silyloxy group is either syn or anti to the newly formed pyrazoline ring. To elucidate the origin of the stereoselectivity, density functional theory (DFT) calculations were carried out for the energy of each transition state structure (TSs) and product. Steric effects were identified as the major determining factors in the diast ...[more]

PMID: 26633338

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