21570-35-4Relevant articles and documents
Multiple Halogenation of Aliphatic C?H Bonds within the Hofmann–L?ffler Manifold
Del Castillo, Estefanía,Martínez, Mario D.,Bosnidou, Alexandra E.,Duhamel, Thomas,O'Broin, Calvin Q.,Zhang, Hongwei,Escudero-Adán, Eduardo C.,Martínez-Belmonte, Marta,Mu?iz, Kilian
supporting information, p. 17225 - 17229 (2018/11/10)
An innovative approach to position-selective polyhalogenation of aliphatic hydrocarbon bonds is presented. The reaction proceeded within the Hofmann-L?ffler manifold with amidyl radicals as the sole mediators to induce selective 1,5- and 1,6-hydrogen-atom transfer followed by halogenation. Multiple halogenation events of up to four innate C?H bond functionalizations were accomplished. The broad applicability of this new entry into polyhalogenation and the resulting synthetic possibilities were demonstrated for a total of 27 different examples including mixed halogenations.
Self-coupling of secondary alcohols by Ni/CeO2 catalyst
Shimura, Katsuya,Kon, Kenichi,Hakim Siddiki,Shimizu, Ken-Ichi
, p. 137 - 142 (2013/07/26)
Supported nickel catalysts are studied for the liquid phase CC self-coupling of aliphatic secondary alcohols under additive free conditions in N2 atmosphere. Among various Ni catalysts, 1 or 3 wt% Ni/CeO 2 catalysts pre-reduced in H2 shows highest yield (94%) of a dimer product (a higher ketone) for the self-coupling of 1-octanol at 130 C, and the catalyst is reused. The catalysts are also effective for self-coupling of various secondary alcohols, providing the first heterogeneous catalytic system for the self-coupling of secondary alcohols under mild conditions. Effects of support material and oxidation state of Ni on the activity are studied and it is found that both CeO2 and metallic Ni are indispensable for the reaction. A possible reaction mechanism is proposed, in which ketones, formed by dehydrogenation of alcohol, undergone Aldol condensation to give α,β-unsaturated ketone which is finally hydrogenated by in situ formed NiH species.
Aggregation pheromones and host kairomones of West Indian sugarcane weevil, Metamasius hemipterus sericeus
Perez,Campos,Chinchilla,Oehlschlager,Gries,Gries,Giblin-Davis,Castrillo,Pena,Duncan,Gonzalez,Pierce Jr.,McDonald,Andrade
, p. 869 - 888 (2007/10/03)
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.
