Isomerès optiques du naftidrofuryl ( = 2-[(naphth-1-yl)méthyl]-3-(tétrahydrofur-2-yl)propanoate de 2-(diéthylamino) éthyle)

Optical Isomers of Naftidrofuryl( = 2-(Diethylamino)ethyl 2-[(Naphth-1-yl)methyl]-3-(tetrahydrofur-2-yl)propanoate) The four optical isomers of naftidrofuryl ( 1 ) were prepared in two ways, by separation and resolution of the two diastereoisomeric racemates and by synthesis from the enantiomers of tetrahydrofuran-2-methanol ( 6 ); see Scheme}. The absolute configuration of one of the isomer as a tartrate monohydrate was established by X-ray crystallography thus allowing the deduction of the absolute configurations of the other three optical isomers.     

A facile synthesis of novel benzofuran-2-yl(9-methyl-9H-carbazol-3-yl)methanones

A facile synthesis of hitherto unreported benzofuran-2-yl(9-methyl-9H-carbazol-3-yl)methanones (3a?Cl) is described. The synthesis mainly relies on the ultrasound-assisted Rap?CStoermer reaction of 3-chloroacetyl-9-methyl-9H-carbazole (1) with a variety of salicylaldehydes, as well as 2-hydroxy-1-naphthaldehyde (2) in CH₃CN, with the presence of PEG-400 as a catalyst. This procedure offers easy access to benzofuran-2-yl(carbazolyl)methanone derivatives in a short reaction time and the products are achieved in good yields.     

N-(9,9-二苯基-9H-芴-2-基)-N,9-二苯基-9H-咔唑-2-胺的合成

以邻溴硝基苯为起始原料,经Suzuki偶联反应、Cadogan关环反应、Ullmam反应、Buchwald反应等合成了目标产物N-(9,9-二苯基-9H-芴-2-基)-N,9-二苯基-9H-咔唑-2-胺,其结构经¹H NMR、 ¹³C NMR和HR-MS(ESI)确证,并采用TG-DSC、 UV-Vis对产物的热稳定性能和光学性能进行了研究。      

2-[(9-苯基)-9H-3-咔唑基]-5-[(9-对甲苯基)-9H-3-咔唑基]吡啶的合成及其光谱性能

以咔唑和2,5-二溴吡啶为初始原料,经Ullmann反应、NBS亲电取代反应和Suzuki偶联等反应,合成了一种新型的磷光配体2-[(9-苯基)-9H-3-咔唑基]-5-[(9-对甲苯基)-9H-3-咔唑基]吡啶(5),其结构经1HNMR,ESI-MS及元素分析表征。研究了5在二氯甲烷中的荧光光谱和紫外吸收光谱。     

Facile Synthesis of Some 3-(Benzimidazol-2-yl)- and 3,6-Di(Benzimidazol-2-yl)-9-ethyl-9H-carbazoles

A simple and efficient synthesis of novel 3-(benzimidazol-2-yl)- and 3,6-di(benzimidazol-2-yl)-9-ethyl-9H-carbazoles is described. The synthetic approach for the preparation of 2-substituted benzimidazoles 4–8 and bis-benzimidazoles 9–12 was achieved by the condensation of carbazole-3-carbaldehyde 2 and carbazole-3,6-dicarbaldehyde 3 with o-phenyldiamines in dimethylformamide or dimethylsulfoxide in moderate to excellent yield. The identities of synthesized compounds were confirmed using ¹H NMR, ¹³C NMR, infrared (IR), and high-resolution mass spectrometry (HRMS).     

Degenerate rearrangement of 9-isopropenyl-9,10-dimethyl-phenanthren-9-yl and 9,10-dimethyl-9-(trans-1-methylprop-1-en-1-yl)phenanthren-9-yl cations

¹H NMR study has shown that long-lived 9-R-9,10-dimethylphenanthren-9-yl cations (R = isopropenyl, trans-1-methylprop-1-en-1-yl) generated in the system HSO₃F-SO₂ClF-CD₂Cl₂ at ?130°C undergo degenerate rearrangement via 1,2-vinyl shifts (ΔG’ = 37 and 39 kJ/mol, respectively, at ?88°C). Analysis of the geometric parameters of the initial structures and transition states calculated by the DFT method indicates that unfavorable steric factors are responsible for the sharp deceleration of 1,2-shifts of the isopropenyl and trans-1-methylprop-1-en-1-yl groups as compared to vinyl and cis-1-methylprop-1-en-1-yl groups, respectively.