Nathan R. Halcovitch

Cross-Coupling of α-carbonyl sulfoxonium ylides with C-H bonds

The functionalization of carbon-hydrogen bonds in non-nucleophilic substrates using α-carbonyl sulfoxonium ylides has not been so far investigated, despite the potential safety advantages that such reagents would provide over either diazo compounds or their in situ precursors. Described herein are the cross-coupling reactions of sulfoxonium ylides with C(sp2 )-H bonds of arenes and heteroarenes in the presence of a rhodium catalyst. The reaction proceeds by a succession of C-H activation, migratory insertion of the ylide into the carbon-metal bond, and protodemetalation, the last step being turnover-limiting. The method is applied to the synthesis of benz[c]acridines when allied to an iridium-catalyzed dehydrative cyclization.

A multicomponent reaction of 2-aminoimidazoles: microwave-assisted synthesis of novel 5-aza-7-deaza-adenines

An efficient and highly selective multicomponent synthesis of 4-aminoimidazo[1,2-a][1,3,5]triazines, which are 5-aza-7-deaza-isosteres of adenine, was developed. The reaction of 2-aminoimidazoles, triethyl orthoformate and cyanamide under microwave irradiation proceeded regioselectively to provide a library of novel 5-aza-7-deaza-adenines in good yields and purity. The developed method was demonstrated to be scalable and highly reproducible in three different monomode microwave reactors. A rearrangement was proposed to explain the high selectivity of the reaction.

μ3-Chlorido-μ2-chlorido-(μ3-pyrrolidine-1-carbo­dithio­ato-κ4S:S,S′:S′)tris­[(tri­ethyl­phosphane-κP)copper(I)]: crystal structure and Hirshfeld surface analysis

The dithiocarbamate ligand chelates one CuI atom and each S atom bridges a second CuI atom and thus, is tetracoordinate. The core of the molecule comprises Cu3Cl2S2 and defines seven corners of a distorted cube.

[N,N-Bis(2-hy­droxy­eth­yl)di­thio­carbamato-κ2S,S′]bis­(tri­phenyl­phosphane-κP)copper(I) chloro­form monosolvate: crystal structure, Hirshfeld surface analysis and solution NMR measurements

A tetrahedral CuP2S2 coordination geometry is found for the CuI ion in the title compound. The dithiocabamate ligand forms symmetric Cu—S bonds. In the crystal, supramolecular dimers of complex molecules are connected via eight-membered {⋯H—O⋯H—O}2 synthons. In addition, the chloroform molecule participates in Cl⋯π(arene) and S⋯Cl interactions.

Crystal structure of bis(μ2-diethyldithiocarbamato-κ3S,S′:S′)-bis(tricyclohexylphosphane-κP)dicopper(I), C46H86Cu2N2P2S4

Abstract C46H86Cu2N2P2S4, triclinic, P1̄ (no. 2), a = 9.9626(3) Å, b = 11.0489(3) Å, c = 12.3604(3) Å, α = 106.205(3)°, β = 99.165(2)°, γ = 100.306(3)°, V = 1253.53(6) Å3, Z = 1, Rgt(F) = 0.0232, wRref(F2) = 0.0555, T = 100(2) K.

Crystal structure of bis(μ2-pyrrolidine-1-carbodithioato-κ3 S,S′:S;κ3S:S:S′)-bis(tricyclohexylphosphane-P)-di-copper(I), C46H82Cu2N2P2S4

Abstract C46H82Cu2N2P2S4, triclinic, P1̄ (no. 2), a = 11.6189(2) Å, b = 12.2846(2) Å, c = 18.1744(2) Å, α = 97.3210(10)°, β = 106.3080(10)°, γ = 99.312(2)°, V = 2415.65(7) Å3, Z = 2, Rgt(F) = 0.025, wRref(F2) = 0.066, T = 100(2) K.

Crystal structure of bis(μ2-di-n-butyldithiocarbamato-κ3S,S′:S;κ3S:S:S′)-hexacarbonyl-di-rhenium(I), C24H36N2O6Re2

Abstract C24H36N2O6Re2, triclinic, P1̅ (no. 2), a = 10.3013(2) Å, b = 11.3471(2) Å, c = 14.5967(3) Å, α = 72.540(2)°, β = 73.074(2)°, γ = 85.369(2)°, V = 1557.05(6) Å3, Z = 2, Rgt(F) = 0.0214, wRref(F2) = 0.0466, T = 100(2) K.

Crystal structure of chlorido-methanol-(N-(2-(oxy)-3-methoxybenzylidene)pyridine-4-carbohydrazonato-κ3O,N,O′)-(4-methylphenyl)methyl-tin(IV), C23H24ClN3O4Sn

Abstract C23H24ClN3O4Sn, triclinic, P1̄ (no. 2), a = 9.7536(2) Å, b = 10.0755(2) Å, c = 12.4215(3) Å, α = 84.928(2)°, β = 72.544(2)°, γ = 74.382(2)°, V = 1121.44(4) Å3, Z = 2, Rgt(F) = 0.021, wRref(F2) = 0.054, T = 100(2) K.

Crystal structure of 7-(4-methylphenyl)imidazo[1,2-a][1,3,5]triazin-4-amine, C12H11N5

Abstract C12H11N5, monoclinic, P21/n (no. 14), a = 7.3455(1) Å, b = 12.2470(1) Å, c = 12.1689(1) Å, β = 103.505(1)°, V = 1064.45(2) Å3, Z = 4, Rgt(F) = 0.0365, wRref(F2) = 0.0987, T = 100 K.

N′-[1-(5-Bromo-2-hydroxyphenyl)ethylidene]isonicotinohydrazide monohydrate:crystal structure and Hirshfeld surface analysis

The organic molecule is twisted with a near orthogonal relationship between the outer rings [dihedral angle = 71.79 (6)°]. Supramolecular ribbons sustained by hydrogen bonding feature in the molecular packing.