Synthesis and characterization of unsaturated diacyl and alkyl-acyl piperazinederivatives
作者:Sait SARI、Seda ÜNALAN、Mehmet YILMAZ
DOI:10.3906/kim-1907-16
日期:——
methods. Acylchlorides 2ed and 2f }were obtained from the reaction of commercially purchased carboxylic acids 3d and 3e with thionyl chloride. Acylchlorides (2g-2j) were synthesized from the reaction of thionyl chloride with carboxylic acids (3d-3g) transformed from hydrolyzation of esters (4a-4d}) obtained as a result of the reaction of triethyl phosphonoacetate with a suitable ketone (acetophenone
Synthesis, X-ray crystal structure and optical properties of novel 2-aryl-3-ethoxycarbonyl-4-phenylpyrido[1,2-a]benzimidazoles
作者:Xia Chen、He Yang、Yanqing Ge、Lei Feng、Jiong Jia、Jianwu Wang
DOI:10.1002/bio.1362
日期:2012.9
A series of novel 2-aryl-3-ethoxycarbonyl-4-phenylpyrido[1,2-a]benzimidazole derivatives were synthesized by the tandem reaction of 2-benzoyl benzimidazole and (Z)-ethyl 4-bromo-3-arylbut-2-enoate in the presence of potassium carbonate. The compounds were characterized using IR, 1H-NMR, 13C-NMR, HRMS and the structure of 6f was further determined by X-ray crystallography. Both absorption and fluorescence
Catalytic hydrogenation of α,β-unsaturated carboxylic acid derivatives using copper(<scp>i</scp>)/N-heterocyclic carbene complexes
作者:Birte M. Zimmermann、Sarah C. K. Kobosil、Johannes F. Teichert
DOI:10.1039/c8cc09853k
日期:——
air-stable copper(I)/N-heterocyclic carbene complex enables the catalytic hydrogenation of enoates and enamides, hitherto unreactive substrates employing homogeneous copper catalysis and H2 as a terminal reducing agent. This atom economic transformation replaces commonly employed hydrosilanes and can also be carried out in an asymmetric fashion.
limited to the construction of tertiarychiralcenters. The asymmetric generation of acyclic products containing all-carbon quaternary stereocenters from substituted 1,3-dienes represents a more challenging, but highly desirable, synthetic process for which there are very few examples. Herein, we report the highly selective copper-catalyzed generation of chiral all-carbon acyclic quaternary stereocenters
A series of chiral beta-aryl-gamma-amino acid ester derivatives were synthesized in high enantioselectivities (93-97% ee) via the Rh-catalyzed asymmetric hydrogenation of gamma-phthalimido-alpha,beta-unsaturated carboxylic acid esters using highly modular chiral BoPhoz-type phosphine-aminophosphineligands. The method has been applied successfully to the synthesis of several chiral pharmaceuticals