ChemInform Abstract: Synthesis of Five-Membered Nitrogen Heterocycles Substituted with a Trifluoromethyl Group.

Abstract Atropisomerism owing to hindered rotation about the N-aryl bond is observed in 4,5-diethyl-2,2,3-trimethyl-1-(o-trifluormethyl)phenyl-2,5-dihydro-1H-1,2,5-azasila-(2) and -azastanna-boroles (5). The compounds 2 and 5 are characterized by elemental analysis, mass spectra and 1H, 11B, 13 C, 29Si and119Sn NMR. The ortho-trifluoromethyl group serves as an additional NMR spectroscopic probe because of “through space” 19F-1H and 19F-13C spin spin coupling. Compound 5 is the first derivative of a 2,5-dihydro-1H-1,2,5-azastannaborol.

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ChemInform Abstract: Generation of 6-(Trifluoromethyl)-4,5-dihydro-2(3H)-pyridone and the Application to Synthesis of Some Fused Nitrogen Heterocycles Carrying a Trifluoromethyl Group on the Bridgehead Position via Radical Cyclization of Dihydropyridones.

ChemInform ◽

10.1002/chin.199736164 ◽

2010 ◽

Vol 28 (36) ◽

pp. no-no

Author(s):

T. OKANO ◽

T. SAKAIDA ◽

S. EGUCHI

Keyword(s):

Nitrogen Heterocycles ◽

Radical Cyclization ◽

Trifluoromethyl Group ◽

Bridgehead Position

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Generation of 6-(Trifluoromethyl)-4,5-dihydro-2(3H)-pyridone and the Application to Synthesis of Some Fused Nitrogen Heterocycles Carrying a Trifluoromethyl Group on the Bridgehead Position via Radical Cyclization of Dihydropyridones

The Journal of Organic Chemistry ◽

10.1021/jo961030g ◽

1996 ◽

Vol 61 (25) ◽

pp. 8826-8830 ◽

Cited By ~ 27

Author(s):

Takashi Okano ◽

Tsutomu Sakaida ◽

Shoji Eguchi

Keyword(s):

Nitrogen Heterocycles ◽

Radical Cyclization ◽

Trifluoromethyl Group ◽

Bridgehead Position

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Hydrogen Cyanide Polymers from the Impact of Comet P/Shoemaker-Levy 9 on Jupiter

International Astronomical Union Colloquium ◽

10.1017/s025292110001469x ◽

1997 ◽

Vol 161 ◽

pp. 179-187

Author(s):

Clifford N. Matthews ◽

Rose A. Pesce-Rodriguez ◽

Shirley A. Liebman

Keyword(s):

Amino Acids ◽

Solar System ◽

Hydrogen Cyanide ◽

Nitrogen Heterocycles ◽

Laboratory Studies ◽

Heterogeneous Solids ◽

The Many ◽

Comet Halley ◽

The Impact ◽

By Products

AbstractHydrogen cyanide polymers – heterogeneous solids ranging in color from yellow to orange to brown to black – may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orangebrown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia, the color observed depending on the concentration of HCN involved. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to α-amino acids. Black polymers and multimers with conjugated ladder structures derived from HCN could also be formed and might well be the source of the many nitrogen heterocycles, adenine included, observed after pyrolysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter might therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized directly from HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.

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