Electron ionization-induced fragmentation of some new dibenzo(d, f)(1,3)dioxepine derivatives

The mass spectrometric behaviour of a series of 6,6-disubstituted dibenzo(d,f)(1,3)dioxepine derivatives have been studied. The fragmentation patterns were described and discussed in detail with the aid of labelled compounds, accurate mass measurements and collisionally induced dissociation experiments performed using an ion trap.     

2-substituted benzofuran fragment ion formation in the electron ionization mass spectra of 6-alkyl- and 6-aryldibenzo(d,f)(1,3)dioxepine derivatives. 1. Spirocyclization of the molecular ions in the gas phase

The formation of 2-substituted benzo[b]furan ions in the electron ionization (EI) mass spectra of a series of 6-alkyl- and 6-aryldibenzo(d,f)(1,3)dioxepines has been studied by means of exact mass measurements and multiple-stage mass spectrometry conditions using an ion trap mass spectrometer. The proposed mechanism of formation of benzo[b]furan ions requires the formation of a spirocyclic cyclohexadienone system, which undergoes elimination of a cyclopentadienone molecule. A parallel with the chemical conversion of arylmethyl-substituted dibenzo(d,f)(1,3)dioxepines into an analogous spirocyclic system was also underlined.     

Brönsted酸性离子液体催化芳香醛和2-甲基喹啉反应合成1,3-二(2-喹啉基)丙烷化合物

以Brönsted酸性离子液体1-乙基-3-丁基咪唑对甲苯磺酸盐为催化剂, 将芳香醛和2-甲基喹啉类化合物在无溶剂或甲苯中于120 ℃反应48 h, 制备了一系列的1,3-二(2-喹啉基)丙烷化合物, 产率56%~92%, 产物结构经核磁共振波谱和高分辨质谱确证. 该方法具有简便易行、 产率较高等特点.     

Synthesis and Crystal Structure of N-[(3aR,4R,4aR,5aS,6S,6aS)-1,3-Dioxooctahydro-4,6-ethenocyclopropa[f]lisoindol-2(1H)-yl]-3-(trifluoromethyl)phenylmethanimine

The crystal structure of the title compound (C19H15F3N2O2, Mr= 360.33) was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P(1), with a = 6.5604(7), b = 13.9614(16), c = 18.1790(18) (A), α = 102.749(7),β = 97.542(6), γ = 94.355(4)°, V= 1600.5(3) (A)3, Z = 4, Dc = 1.495 g/cm3, λ(MoKα) = 0.71070, F(000) = 744, μ(MoKα) = 0.122mm-1, R = 0.0434 and wR = 0.1051. A total of 7590 unique reflections were collected, of which 5429 with |F|2 ≥ 2σ|F|2 were observed. The two cyclohexene rings in the molecule adopt boat-boat conformations with the deviations of ring atoms C(9) and C10 from the C(5)/C(6)/C(7)/C(8) plane (Ⅰ) by 1.1204 (0.0023) and 1.1132 (0.0023) (A), respectively, whereas from the C(2)/C(3)/C(5)/C(8)plane (Ⅱ) by 1.1627 (0.0022) and 1.1818 (0.0021) (A), respectively. In the cyclopropane and lactam rings, atoms C(11) and N(1) point towards the double bond of C(9)-C(10) and the dihedral angle between the ring plane (Ⅲ) containing C(1), C(2), C(3) and C(4) and plane (Ⅳ) consisting of C(6),C(7) and C(11) is 55.76 (0.07)°. The dihedral angles between planes Ⅳ and Ⅰ and Ⅱ and Ⅲ are 63.58 (0.07)° and 58.10 (0.06)°, respectively. The dihedral angle between the benzene ring C(13)～C(18) and plane Ⅳ is 42.41 (0.06)°.