ISSN:
1573-9171
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Conclusions 1. The influence of pressure on asymmetric diene condensation of butadiene with di-(−)-menthyl fumarate was investigated. At atmospheric pressure (70°), the optical yield is equal to 0; at 5000 kg/cm2, an excess of the di-(−)-menthyl ester of (+)-Δ4-trans-cyclohexene-1,2-dicarboxylic acid is formed with an optical yield of 4.7%. 2. In the reaction studied, the transition state in the formation of the dimenthyl ester of the (+)-acid is characterized by lower values of the energy, entropy, and volume than in the case of the (−)-acid. 3. The role of the change in the free volume as a component of the volume effect of activation was discussed. It was concluded that there is a relationship between the steric hindrance of the reaction and the change in the free volume in the formation of the transition state. 4. Hypotheses are expressed on the principles of the influence of pressure on asymmetric synthesis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00860003
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