Sentence examples for migratory aptitude of from inspiring English sources

In the case of 1-phenylbutan-2-one (16), where both α-carbon atoms are equally substituted, the migratory aptitude of the α-carbon atoms seemed to be primarily determined by the higher nucleophilicity of the α-carbon bonded to the aromatic ring due to its donating electronic effect compared with the methyl group.

This property is responsible for higher migratory aptitude of tertiary carbon atoms over secondary and primary.

The relative migratory aptitude of different amide substituents was therefore probed further by using ynamides 1 a– i (Table 2).

The rate of 1,2-carboboration is found by experiment (thienyl>phenyl) and calculations (phenyl>methyl) to be strongly dependant on the migratory aptitude of the hydrocarbyl group.

-Dihydrocarvone -14 is transformed into lactone 15 with regard to the higher migratory aptitude of tertiary carbon atom adjacent to the carbonyl group.

DFT calculations at the M06-2X/6-311G d,p /PCM DCM) level confirm that the higher migratory aptitude of Ph versus Me leads to a lower barrier to 1,2-carboboration relative to 1,1-carboboration.

To probe the effect of migratory aptitude further the calculated transition state energies for the carboboration of 2-butyne with the hypothetical borenium cation QOBMe+ was examined.

Thus not only reaction outcome (1,1 versus 1,2-carboboration), but also rate of reaction is controlled by the relative migratory aptitude.

We surmised that the relative rarity of 1,2-carboborations is due to the use, historically, of R groups with an intrinsically low migratory aptitude (e.g., R=1° alkyl or C6F5 in RB(C6F5 2) 6 and it is this low migratory propensity that leads to high barriers to 1,2-carboboration.

Thus, for migratory aptitude phenyl≫C6F5 and 1° alkyl.

Migratory aptitude is particularly well-defined in the Baeyer Villager reaction (also involving a cationic transition state and formal migration of a hydrocarbyl anion) and corresponds to the availability of bonding electrons in the moiety undergoing migration to donate into a σ* orbital (in carboboration, it is donation to the formally empty p z orbital in the vinyl cation).