- Preparation of ketones via the palladium-catalyzed cross-coupling of acid chlorides with trialkylboranes
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Trialkylboranes react with acid chlorides in the presence of palladium to generate alkyl and aryl ketones in good yields. (C) 2000 Elsevier Science Ltd.
- Kabalka, George W.,Malladi, Rama R.,Tejedor, David,Kelley, Shane
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p. 999 - 1001
(2007/10/03)
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- Aggregation pheromones and host kairomones of West Indian sugarcane weevil, Metamasius hemipterus sericeus
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Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses and coupled GC-mass spectrometry (MS) of volatiles produced by male and female West Indian sugarcane weevils (WISW), Metamasius hemipterus sericeus (Oliv.), revealed eight male specific, EAD-active compounds: 3-pentanol (1), 2-methyl-4-heptanol (2), 2-methyl-4-octanol (3) 4-methyl-5-nonanol (4), and the corresponding ketones. In field experiments in Florida, alcohols 1-4 in combination with sugarcane were most attractive, whereas addition of the ketones or replacement of alcohols with ketones significantly reduced attraction. In Costa Rica field experiments testing alcohols 1-4 singly and in all binary, ternary, and quaternary combinations revealed 4 in combination with 2 was the major aggregation pheromone, equally attracting male and female WISW. Stereoisomeric 4 and (4S,5S)-4, the only isomer produced by WISW, were equally attractive. Addition of 4S-, 4R- or (±)-2 to (4S,5S)-4 significantly enhanced attraction Sugarcane stalks in combination with 2 plus 4 (ratio of 1:8) were highly synergistic, whereas EAD-active sugarcane volatiles ethyl acetate, ethyl propionate, or ethyl butyrate only moderately increased attractiveness of the pheromone lure.
- Perez,Campos,Chinchilla,Oehlschlager,Gries,Gries,Giblin-Davis,Castrillo,Pena,Duncan,Gonzalez,Pierce Jr.,McDonald,Andrade
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p. 869 - 888
(2007/10/03)
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- Certain sulfonamide heterobicyclic platelet activating factor antagonists
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Compounds of general formula I; STR1 wherein: A1 is =N--, =CH-- or =CR1 --; A2 is =N--, =CH-- or =CR2 --; provided that, when one of A1 and A2 is a nitrogen atom, the other of A1 and A2 is other than a nitrogen atom; wherein the other variables are as defined in the specification and their pharmaceutically and veterinarily acceptable acid addition salts and hydrates are antagonists of platelet activating factor (PAF) and as such are useful in the treatment or amelioration of various diseases or disorders mediated by PAF.
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- The Synthesis of Ketones via α-Silyl Sulphides
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α-Phenylthiosilanes (2) have been prepared by alkylation of the anion (4) derived from the 1-phenylthio-1-trimethylsilylalkane (1).These anions (4) have benn prepared by a variety of methods including, direct deprotonation of (1), displacement of a phenylthio group by lithium naphthalenide addition of an alkyl-lithium to 1-phenylthio-1-trimethylsilylethene (7), and transmetallation of a tributylstannyl moiety.The formation of an alkyl-lithium by reaction of lithium naphthalenide with a phenyl sulphide provided an additional route to (2) from bis(phenylthio)acetals (8).An alternative path to the α-phenylthiosilanes (2) was to reduce the corresponding α-phenylsulphonylsilane (15); these, in turn, being readily available from alkylation or silylation of α-sulphonyl anions.The α-phenylthiosilanes (2) were converted into the O-trimethylsilylphenylthioacetal (18) by the sila-Pummerer rearrangement, although this was complicated by vinyl sulphide (20) formation in certain cases.Subsequent hydrolysis of (18) and (20) gave the ketone (3).
- Ager, David J.
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p. 195 - 204
(2007/10/02)
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