Stereochemical control in the intramolecular Diels-Alder reaction. 2. Structural and electronic effects on reactivity and selectivity

1982 ◽  
Vol 104 (4) ◽  
pp. 1033-1041 ◽  
Author(s):  
Robert K. Boeckman ◽  
Soo Sung Ko
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Electronic Effects ◽  
Stereochemical Control ◽  
Diels Alder Reaction

ELECTRONIC EFFECTS AND RATES IN THE DIELS-ALDER REACTION

1952 ◽  
Vol 17 (2) ◽  
pp. 201-206 ◽  
Author(s):  
JOSEPH J. DUDKOWSKI ◽  
ERNEST I. BECKER
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Electronic Effects ◽  
Diels Alder Reaction

Stereochemical control by an allylic substitutent of an acyclic dienophile in the Diels-Alder reaction

1982 ◽  
Vol 104 (4) ◽  
pp. 1106-1107 ◽  
Author(s):  
Richard W. Franck ◽  
Thomas V. John ◽  
Kazimierz Olejniczak ◽  
John F. Blount
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Stereochemical Control ◽  
Diels Alder Reaction

Organic reactions in liquid crystalline solvents. 2. An investigation into the use of liquid crystalline solvents to effect stereochemical control in the Diels–Alder reaction

1985 ◽  
Vol 63 (10) ◽  
pp. 2736-2741 ◽  
Author(s):  
William J. Leigh
Keyword(s):  
Liquid Crystalline ◽  
Transition States ◽  
Alder Reaction ◽  
Diels Alder ◽  
Shape Transition ◽  
Bimolecular Reactions ◽  
Solvent Phase ◽  
Stereochemical Control ◽  
Diels Alder Reaction ◽  
Liquid Crystalline Phases

The possibility of using liquid crystalline solvents to control the stereospecificity of bimolecular reactions as a result of differences in liquid crystalline solvation of the various possible transition states has been examined. The Diels–Alder reactions of 2,5-dimethyl-3,4-diphenylcyclopentadienone with four dienophiles of varying steric size (cyclopentene, cycloheptene, indene, and acenaphthylene) have been carried out in benzene, cholesteryl nonanoate (isotropic), cholesteryl propionate (cholesteric), and 4-ethyl-4′-(4-pentylcyclohexyl)biphenyl (smectic) at 105 °C. In spite of very large differences in steric solvation requirements for the endo- (globular in shape) and exo- (plate-like in shape) transition states in these reactions, no variation in product ratio with solvent phase is observed in any case.The inability of the ordered liquid crystalline phases to differentiate between endo- and exo-transition states in the Diels–Alder reactions investigated is rationalized as being the possible result of several factors. The most important of these are believed to be free volume effects, owing to both inefficient steric solvation of the bulky diene and volume contraction in the transition states for cycloaddition.

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