Über die Synthese von Phosphamidon und seinen Abbau in Pflanzen
作者:R. Anliker、E. Beriger、M. Geiger、K. Schmid
DOI:10.1002/hlca.19610440621
日期:——
The synthesis of phosphamidon, a new systemic insecticide, is describcd. By use of the 14C-labeled compound it is shown that in the bean plant phosphamidon undergoes rapid degradation, during which traces of the metabolites desethylphosphamidon,α-chloroacetoaceto-diethylamide, and α-chloroacetoaceto-ethylamide only are detectable. In order to explain the mechanism of the degradation reactions, the
Hydrogen Peroxide or Peracetic Acid Mediated Self-Titrating α-Halogenation of 1,3-Dicarbonyl Compounds
作者:Hasim Ibrahim、Ramulu Akula、Marc Galligan
DOI:10.1055/s-0030-1258367
日期:2011.1
Efficient oxidative α-halogenation of 1,3-dicarbonylcompounds has been achieved by employing a system comprising of sub-stoichiometric amounts of TiX4 (X = Cl, Br) in conjunction with environmentally benign hydrogen peroxide (H2O2) or peracetic acid (MeCO3H) as the oxidants. The end point of the reaction is accompanied by a sharp colour change. halogenation - peroxides - titanium - halides - electrophilic
通过使用包含亚化学计量量的TiX 4(X = Cl,Br)以及环境友好的过氧化氢(H 2 O 2)或过氧乙酸的系统,可以实现1,3-二羰基化合物的有效氧化α-卤化酸(MeCO 3 H)作为氧化剂。反应的终点伴随着急剧的颜色变化。 卤化-过氧化物-钛-卤化物-亲电子
Umpolung of halide reactivity: efficient (diacetoxyiodo)benzene-mediated electrophilic α-halogenation of 1,3-dicarbonyl compounds
作者:Ramulu Akula、Marc Galligan、Hasim Ibrahim
DOI:10.1039/b915348a
日期:——
An efficient high-yielding (diacetoxyiodo)benzene-mediated α-halogenation of 1,3-dicarbonyl compounds utilising titanium tetrahalides as the halide source has been developed.
Highly Stereoselective Synthesis of <i>an</i><i>ti</i>-N-Protected-α-Amino Epoxides
作者:Robert V. Hoffman、Warren S. Weiner、Najib Maslouh
DOI:10.1021/jo010319h
日期:2001.8.1
A simple and efficient method for the synthesis of anti-N-protected amino epoxides from carbamate-protected amino acids is described. The two key steps are the monobromination of a beta -ketoester and chelation-controlled reduction of a bromomethyl ketone intermediate. Good overall yields, high diastereoselectivity, and excellent functional group compatibility are characteristic.
Synthesis of Enantioenriched α,α-Dichloro- and α,α-Difluoro-β-Hydroxy Esters and Amides by Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation
α-dihalogeno β-hydroxy esters or amides by using commercially available Noyori’s complex [RuCl(p-cymene)(R,R)-TsDPEN] as a catalyst (S/C = 100−200) in the asymmetrictransferhydrogenation of the corresponding ketones. Moderate to high yields (up to 99%) and excellent enantioselectivities (up to >99% ee) were achieved for a series of variously substituted dichloro and difluoro β-hydroxy esters and amides.
通过使用市售的Noyori配合物[RuCl(p- Cymene)(R,R)-TsDPEN]作为催化剂(S / C = 100-200)在相应的酮的不对称转移氢化中。对于一系列不同取代的二氯和二氟β-羟基酯和酰胺,可实现中等至高收率(高达99%)和出色的对映选择性(高达> 99%ee)。