The Diels-Alder reaction represents a promising tool for use in
asymmetric synthesis. The reaction involves a rigid transition state
that facilitates the formation of one diastereomeric transition state
and is reversible. This satisfies two necessary criteria for
asymmetric synthesis.
The Diels-Alder reactions of 1,l-dialkylspiro[2.4]-4,6- heptadienes
with maleic anhydride and p-benzoquinone...
The tosylhydrazones of exo-3-deuteriocamphor and 2- deuterio-2,4-dimethy1-3-pentanone were treated with Nbromosuccinimide (NBS) and pyruvic acid to regenerate the parent ketones. The ketones from the pyruvic acid cleavage show a significant loss of deuterium. The ketones from the NBS cleavage show no loss of deuterium, indicating that stereochemical integrity at. C[subscript...
The photochemistry of aldicarb and two related compounds,
0-(methylcarbamoyl) isobutyraldehyde oxime and 0-(methylcarbamoyl)
trimethylacetaldehyde oxime was explored under laboratory
conditions. Upon irradiation aldicarb decomposed rapidly to
methylamine, dimethylamine, tetramethylsuccinonitrile, and
1-methylthio-2, 3-dicyano-2, 3-dimethylbutane. The other two
compounds decomposed only after a long period of irradiation. The
difference in reactivity was...
Intramolecular cyclization of organometallic compounds represents
a promising tool for synthesis in general. The use of strategically-
placed heteroatoms in the cyclizing molecule can influence
the stereochemistry and/or efficiency of an organometallic cyclization
while providing for functionality in the cyclic product.
The work described herein first concerns cyclizations of organolithiums....