Abstract: Disclosed is a process for the coupling of a Grignard reagent RMgX with an allylic halide in the presence of a dipolar aprotic solvent wherein the improvement, for obtaining improved yield and selectivity, comprises adding a catalyst to said Grignard or allylic halide and then carrying out the coupling reaction by the addition of the Grignard reagent to the allylic halide, said reaction being characterized by the displacement at the gamma position (relative to the halide) of the allylic halide with R of the Grignard reagent, migration of the allylic double bond in the direction of the halogen atom and loss of halogen. The present invention also resides in the discovery of certain novel procedures for the synthesis of Vitamin E. Specific embodiments of this aspect of the invention reside in the syntheses of 6,7-dehydrophytol, 10,11-dihydrofarnesene, phytone, hexahydropseudoionone, and related compounds as precursors for Vitamin E.
Abstract: Disclosed is a process for the coupling of a Grignard reagent RMgX with an allylic halide in the presence of a dipolar aprotic solvent wherein the improvement, for obtaining improved yield and selectivity, comprises adding a catalyst to said Grignard or allylic halide and then carrying out the coupling reaction by the addition of the Grignard reagent to the allylic halide, said reaction being characterized by the displacement at the gamma position (relative to the halide) of the allylic halide with R of the Grignard reagent, migration of the allylic double bond in the direction of the halogen atom and loss of halogen. The present invention also resides in the discovery of certain novel procedures for the synthesis of Vitamin E. Specific embodiments of this aspect of the invention reside in the syntheses of 6,7-dehydrophytol, 10,11-dihydrofarnesene, phytone, hexahydropseudoionone, and related compounds as precursors for Vitamin E.
Abstract: Tertiary allylic amines are obtained from vinylic halides and olefins, and substituted derivatives thereof, by reacting said halide with a mono-, di-, or tri-substituted olefin and an unhindered basic secondary amine in the presence of a palladium catalyst.
Abstract: New dehydrotocopherols, namely cis- and trans- 3',4'-dehydrotocopherol; cis- and trans- 4',5'-dehydrotocopherol; and 4',4'-a-dehydrotocopherol, and new didehydrotocopherols, namely cis- and trans- 3',4'-11',12'-didehydrotocopherol; cis- and trans- 4',5'-11',12'-didehydrotocopherol; and 4',4'a-11',12'-didehydrotocopherol, are useful intermediates in the preparation of Vitamin E.These intermediates are prepared by reacting trimethylhydroquinone under acid catalysis with certain C.sub.20 intermediates, namely: ##STR1## where R represnts a 3,7-dimethyloctyl or a 3,7-dimethyl-6-octenyl radical and X is halogen, hydroxyl, acetate, C.sub.1-4 alkanoate, C.sub.3-4 alkenoate, aralkenoate and benzoate.