Double hepatomesenteric artery a rare anatomical variant
摘要:
A case of a "double hepatomesenteric artery", i.e. two persisting hepatic arteries arising from the superior mesenteric artery, is reported. Also observed was a lack of systematisation of the pancreaticoduodenal arteries. The variant, which does not appear to have been previously reported in the literature, was observed when dissecting the vessels of the duodenal bulb in a preserved male cadaver injected with neoprene latex. Its embryological origin, as well as the clinical, radiological (diagnostic or interventional) and surgical implications, are discussed.
Metal exchange between an electrogenerated organonickel species and zinc halide: application to an electrochemical, nickel-catalyzed Reformatsky reaction
摘要:
The mechanism of the electroreductive coupling of alpha-chloro esters or alpha-chloro nitriles with carbonyl compounds by the means of a sacrificial zinc anode and a nickel catalyst was elucidated by electroanalytical techniques. The mechanism involved reduction of a Ni(II) complex to a Ni(0) complex, oxidative addition of the alpha-chloro ester to the Ni(0) complex, and a Zn(II)/Ni(II) exchange, leading to an organozinc Reformatsky reagent. The electrosynthesis of various beta-hydroxy esters, beta-hydroxy nitriles, and 2,3-epoxy esters was successfully achieved under extremely mild conditions.
Organozinc compounds derived from α-bromonitriles are readily prepared in solution in tetrahydrofuran (THF) and exist in the C metallated form. They condense normally with aldehydes and saturated ketones. A number of new β-hydroxy-nitriles are described. The addition of conjugated unsaturated ketones results in the formation of β-hydroxynitriles or ketonitriles, depending on the nature of the initial
Reformatsky-type reactions have been performed efficiently using an electroassisted iron-complex catalysis. Valuable product such as beta-hydroxyesters, ketones or nitriles are thus prepared with high yields.
Addition of α-Halo-substituted Carbonitriles to and AldehydesKetones in the Presence of Iron Pentacarbonyl
作者:T. T. Vasil'eva、N. A. Kuz'mina、O. V. Chakhovskaya、N. E. Mysova、A. B. Terent'ev
DOI:10.1023/b:rujo.0000034937.39138.2a
日期:2004.2
Halo-substituted carbonitriles in the presence of iron pentacarbonyl react with aldehydes and ketones by Reformatsky reaction type. In contract to halo-substituted esters the nitriles are considerably more reactive toward ketones than aldehydes. At the same time the structure and yield of products obtained from both nitriles and esters are strongly and similarly affected by the character of the para-substituents in the benzaldehyde.
Metal exchange between an electrogenerated organonickel species and zinc halide: application to an electrochemical, nickel-catalyzed Reformatsky reaction
作者:Annie Conan、Soline Sibille、Jacques Perichon
DOI:10.1021/jo00006a012
日期:1991.3
The mechanism of the electroreductive coupling of alpha-chloro esters or alpha-chloro nitriles with carbonyl compounds by the means of a sacrificial zinc anode and a nickel catalyst was elucidated by electroanalytical techniques. The mechanism involved reduction of a Ni(II) complex to a Ni(0) complex, oxidative addition of the alpha-chloro ester to the Ni(0) complex, and a Zn(II)/Ni(II) exchange, leading to an organozinc Reformatsky reagent. The electrosynthesis of various beta-hydroxy esters, beta-hydroxy nitriles, and 2,3-epoxy esters was successfully achieved under extremely mild conditions.
Double hepatomesenteric artery a rare anatomical variant
A case of a "double hepatomesenteric artery", i.e. two persisting hepatic arteries arising from the superior mesenteric artery, is reported. Also observed was a lack of systematisation of the pancreaticoduodenal arteries. The variant, which does not appear to have been previously reported in the literature, was observed when dissecting the vessels of the duodenal bulb in a preserved male cadaver injected with neoprene latex. Its embryological origin, as well as the clinical, radiological (diagnostic or interventional) and surgical implications, are discussed.