Crystal structure of 5,8-dimethyl-6-(p-dimethylaminophenylethynyl)-2,2- diphenyl-2H-1-benzopyran, C33H29NO

Abstract

C33H29NO, monoclinic, P21/a (no. 14), a =1 6.832(3) A, b =9 .325(2) A, c =1 6.999(3) A, / =1 05.03(6)°, V =2 576.9(9) A 3 , Z =4 , Rgt(F) =0 .0407, wRref(F 2 ) =0 .2999, T =2 93 K. Source of material To as olution of 4-(5,8-dimethyl-2,2-diphenyl-2H-chromen-6yl)-2-methylbut-3-yn-2-ol (201 mg, 0,51 mmol) in dry toluene (10 mL) was adde dt he commercial available 4-bromo-N,Ndimethylamine (112 mg ,0 .56 mmol), and the mixture was degassed under argon. Then, ad eaerated aqueous solution of 5.5N NaOH (10 mL), (C6H5-CH2NEt3)Cl (3.5 mg, 0.015 mmol), Pd(PPh3)4 (2 9m g, 0.02 5m mol) and CuI (4.8 mg, 0.025 mmol) were successively added. Th eh eterogeneous mixture was stirred at 70 °C fo r4 h( Thin Laye rC hromatography (TLC) monitoring: cyclohexane/CH2Cl2 :5 0/50). After complete disappearance of the propargylic alcohol, the crude mixture was cooled down to room temperatur ea nd decanted .T he separate aqueou sl ayers were extracte dw ith Et2 O( 3 %10 mL). Th ec ombined organic layers were washed with as aturated NH4Cl aqueou ss olutio n( 3 %15 mL )u ntil neutralisation, dried over MgSO4 and evaporated under reduced pressure. The crude product was purified by column chromatography (SiO2 ;c yclohexane/CH2Cl2 :1 00/0 to 30/70) to afford the desired compound as aw hite powder (148 mg, yield 64%). Crystals appropriate for data collection were obtained after slow evaporation from hexane/CH2Cl2 solution at 298K.