1.(E)-3,3'-(Diazene-1,2-di-yl)bis-(1-methyl-1,4,5,6-tetra-hydro-pyrrolo-[3,4-c]pyrazol-5-ium) dinitrate dihydrate.
Chen JM1, Zhao H. Acta Crystallogr Sect E Struct Rep Online. 2012 Jan;68(Pt 1):o151. doi: 10.1107/S1600536811053347. Epub 2011 Dec 17.
The title compound, C(12)H(18)N(8) (2+)·2NO(3) (-)·2H(2)O, was synthesized unexpectedly from 3-amino-1-methyl-1,4,5,6-tetra-hydro-pyrrolo-[3,4-c]pyrazol-5-ium chloride and cerium(IV) ammonium nitrate. The cation has a crystallographically imposed centre of symmetry. In the crystal, the ions and water mol-ecules are linked via O-H⋯N, N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network.
2.Dissociation of the disilatricyclic diallylic dianion [(C4Ph4SiMe)2]-2 to the silole anion [MeSiC4Ph4]- by halide ion coordination or halide ion nucleophilic substitution at the silicon atom.
Hong JH1. Molecules. 2011 Oct 10;16(10):8451-62. doi: 10.3390/molecules16108451.
The reductive cleavage of the Si-Si bond in 1,1-bis(1-methyl-2,3,4,5-tetraphenyl-1-silacyclopentadiene) [(C(4)Ph(4)SiMe)(2)] (1) with either Li or Na in THF gives the silole anion [MeSiC(4)Ph(4)]- (2). The head-to-tail dimerization of the silole anion 2 gives crystals of the disilatricyclic diallylic dianion [(C(4)Ph(4)SiMe)(2)]-2 (3). The derivatization of 3 (crystals) with bromoethane (gas) under reduced pressure provides [(MeSiC(4)Ph(4)Et)(2)] (4) quantitatively. The reverse addition of 3 in THF to trimethylsilyl chloride, hydrogen chloride, and bromoethane in THF gives 1-methyl-1-trimethylsilyl-1-silole [Me(3)SiMeSiC(4)Ph(4)] (6), 1-methyl-2,3,4,5-tetraphenyl-1-silacyclo-3-pentenyl-1-methyl-1-silole [C(4)Ph(4)H(2)SiMe-MeSiC(4)Ph(4)] (7), and 1-methyl-2,5-diethyl-2,3,4,5-tetraphenyl-1-silacyclo-3-pentenyl-1-methyl-1-silole [C(4)Ph(4)Et(2)SiMe-MeSiC(4)Ph(4)] (8), respectively. The reaction products unambiguously suggest that the silole anion [MeSiC(4)Ph(4)]- is generated by coordination of the chloride ion at the silicon atom in 3 or by the nucleophilic substitution of either chloride or bromide ion at one of two silicon atoms in 3.
3.Simultaneous analysis of 1,2,3,4-tetrahydroisoquinolines by high-performance liquid chromatography using 4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl chloride as a fluorescent labeling reagent.
Inoue H1, Matsubara D, Tsuruta Y. J Chromatogr B Analyt Technol Biomed Life Sci. 2008 May 1;867(1):32-6. doi: 10.1016/j.jchromb.2008.03.002. Epub 2008 Mar 8.
A highly sensitive high-performance liquid chromatographic method for the simultaneous analysis of 1,2,3,4-tetrahydroisoquinolines (TIQs) in the rat brain was developed. 1,2,3,4-Tetrahydroisoquinoline (TIQ), 1-methyl-1,2,3,4-tetrahydroisoquinoline (1-MeTIQ) and 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1-BeTIQ) were derivatized with 4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl chloride to produce fluorescent sulfonamides. The labeling reaction was carried out at 50 degrees C for 15 min at pH 8.5. The fluorescent derivatives were separated on a reversed-phase column by gradient elution using (A) water-(B) acetonitrile/methanol (55:45) at 55 degrees C and detected by fluorescence measurement at 318 nm (excitation) and 398 nm (emission). The detection limits (signal-to-noise ratio=3) were 8-9 fmol per injection. The relative standard deviations (n=6) of TIQs were 2.6-10.5% and the recoveries were 87.6, 101.8 and 75.2%, respectively.
4.The surprising nucleophilic addition of aminochlorocarbenes to diethyl acetylenedicarboxylate and to oxalyl chloride: quinolines and benzo[1,4]diazepines from N-alkylformanilides and oxalyl chloride in the presence of Hünig's base.
Cheng Y1, Yang H, Meth-Cohn O. Org Biomol Chem. 2003 Oct 21;1(20):3605-10.
Vilsmeier reagents derived from N-methylformanilides undergo ready deprotonation with Hünig's base. In xylene, the derived nucleophilic arylaminochlorocarbenes bearing 4-methyl- and 4-methoxy-substituents react with acetylenedicarboxylates to give 2-(2-chloro-1,2-bis(ethoxycarbonyl)vinyl)-3,4-bis(ethoxycarbonyl)-1-methyl-1,2-dihydroquinolines while most derivatives react with oxalyl chloride to give substituted 1-methyl-4 phenylbenzo[f][1,4]diazepine-2,3-dicarboxylic anhydrides.