- Total synthesis of (±)-dysidiolide
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The total synthesis of (±)-dysidiolide was accomplished with a high level of intramolecular stereo-induction. Methylation of 6-carboethoxy-3-chloro-5-methyl-cyclohex-2-enone provided 33 bearing the 6,7-trans-dimethyl substitution of the C6-C11 B-ring. Diastereoselective conjugate addition upon enone 34 installed the C11 stereogenic center. Annulation then provided an A-ring enone (23), a substrate for a challenging conjugate addition of the branched pentenyl side chain. The combination of tri-n-butylphosphine, boron trifluoride etherate, and a dialkylcuprate uniquely effected conjugate addition to yield 58. Incorporation of the hydroxybutenolide-containing side chain completed the total synthesis and established the viability of a general approach for the preparation of the isolabdanoid terpene system.
- Demeke, Damtew,Forsyth, Craig J
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p. 6531 - 6544
(2007/10/03)
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- Pheromone Synthesis, CLXIV. Synthesis of (2S,6Z)-6,8-Nonadien-2-ol, a Pheromone Component of the Leafminer Nepticula malella, and Its Antipode
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Both the enantiomers of (Z)-6,8-nonadien-2-ol were synthesized via lipase-catalyzed asymmetric hydrolysis of the acetate of its racemate, which was prepared from ethyl levulinate. - Key Words: Leafminer / Lipases / Nepticula malella / Pheromones / 6,8-Nonadien-2-ol, (2S,6Z),(2R,6Z)-
- Mori, Kenji,Ogita, Haruhisa
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p. 1065 - 1068
(2007/10/02)
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- SYNTHESIS OF THE PROPIONATES OF (2R,8R)- AND (2RS,8R)-8-METHYL-2-DECANOL, THE ATTRACTANTS OF THE WESTERN CORN ROOTWORM
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The propionate of (2R,8R)-8-methyl-2-decanol, (2R,8R)-1, an attractant of the western corn rootworm, Diabrotica virgifera Le Conte, has been prepared by a synthetic route in which enantiomerically pure methyl hydrogen (R)-3-methylglutarate, (R)-2, and (S)-glutamic acid, (S)-3, have been used as chiral precursors.In this convergent synthesis, (R)-2 and (S)-3 have been stereospecifically converted into (R)-1-bromo-3-methylpentane, (R)-4, and (R)-1,4-pentanediol, (R)-5, respectively.An analogous synthetic scheme has been followed to prepare biologically active (2RS, 8R)-1 starting from (R)-4 and racemic 5.
- Carpita, Adriano,Chini, Marco,Rossi, Renzo
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