[DE] EISEN- ODER KOBALT-KATALYSIERTE KOHLENSTOFF-KOHLENSTOFF-KUPPLUNGSREAKTION VON ARYLEN, ALKENEN UND ALKINEN MIT KUPFERREAGENZIEN [EN] IRON OR COBALT-CATALYZED CARBON-CARBON COUPLING REACTION OF ARYLS, ALKENES AND ALKINES WITH COPPER REAGENTS [FR] REACTION DE COUPLAGE CARBONE-CARBONE, CATALYSEES PAR DU FER OU DU COBALT, D'ARYLES, D'ALCENES ET D'ALKINES AVEC DES REACTIFS DE CUIVRE
Highly E-selective solvent-free Horner–Wadsworth–Emmons reaction catalyzed by DBU
作者:Kaori Ando、Kyohei Yamada
DOI:10.1039/c1gc15134g
日期:——
The solvent-free Horner–Wadsworth–Emmons reaction of triethylphosphonoacetate with a variety of aldehydes was catalyzed by DBU in the presence of K2CO3 to give E-α,β-unsaturated esters highly selectively (99:1 for most of the reactions). The reaction with ketones gave trisubstituted olefins with good to high E-selectivity by DBU-Cs2CO3.
这 溶剂无Horner–Wadsworth–Emmons的反应 膦酸三乙酯 与各种 醛类DBU在K 2 CO 3的存在下催化得到E -α,β-不饱和酯类高度选择性(大多数反应为99 :1)。与之反应酮类 给出三取代 烯烃DBU-Cs 2 CO 3具有良好的电子选择性,甚至具有很高的电子选择性。
Selective Iron-Catalyzed Cross-Coupling Reactions of Grignard Reagents with Enol Triflates, Acid Chlorides, and Dichloroarenes
Cheap, readily available, air stable, nontoxic, and environmentally benign iron salts such as Fe(acac)3 are excellent precatalysts for the cross-coupling of Grignardreagents with alkenyl triflates and acid chlorides. Moreover, it is shown that dichloroarene and -heteroarene derivatives as the substrates can be selectively monoalkylated by this method. All cross-coupling reactions proceed very rapidly
廉价,容易获得,空气稳定,无毒且对环境无害的铁盐,例如Fe(acac)3是格氏试剂与链烯基三氟甲磺酸酯和酰氯交叉偶联的出色的预催化剂。此外,显示出通过该方法可以将作为底物的二氯亚芳基和-杂亚芳基衍生物选择性地单烷基化。所有交叉偶联反应在特别温和的条件下均能非常快速地进行,结果证明与两个反应伙伴中的各种官能团均相容。对制备结果的详细分析表明,铁催化的碳键形成可以通过不同的途径发生。因此,甲基卤化镁的反应可能包含铁酸盐配合物作为活性成分,而格氏试剂与两个或多个碳原子的反应则受到形式组成[Fe(MgX)2 ]的高度还原的铁簇的影响。n原位生成。使用复杂的[Me 4 Fe] Li 2的对照实验证实了这一解释。
Copper-Photocatalyzed <i>Contra</i>-Thermodynamic Isomerization of Polarized Alkenes
The contra-thermodynamic isomerization of α- and β-substituted cinnamate derivatives catalyzed by the Cu(OAc)2/rac-BINAP complex under blue light irradiation is reported. The use of an oxazolidinone template, which favored the complexation of the copper catalyst to the substrate, allowed the E → Z isomerization of the catalytically formed chromophore under simple and robust reaction conditions in good
A chiral phenol–NHC ligand enabled the copper-catalyzed enantioselectiveconjugate reduction of α,β-unsaturatedesters. The phenol moiety of the chiral NHC ligand played a critical role in producing the enantiomerically enriched products. The catalyst worked well for various (Z)-isomer substrates. Opposite enantiomers were obtained from (Z)- and (E)-isomers, with a higher enantiomeric excess from the
Baclofen (1) is a potent and selective agonist for bicuculline-insensitive GABA(B) receptors and is used clinically as an antispastic and muscle relaxant agent. In the search for new bioactive chemical entities that bind specifically to GABA(B) receptors, we report here the synthesis of certain baclofen homologues, namely (R,S)-5-amino-3-arylpentanoic acid hydrochlorides (R,S)-1a-h as well as (R,S