Methyl-cyclo-hexane

During the first European Tracer Experiment (ETEX-1) a non-depositing tracer gas (Perflouro-Methyl-Cyclo-Hexane) was emitted from a site in Northern France (Brittany (2°00 30", 48°03 30")). The average emission rate was 7.95 g s and it commenced on 23 October at 16 00 UTC lasting for 11 h and 50 min. The spatial and temporal development of the tracer cloud was measured at 168 measurement stations in Europe and both real time and retrospective model inter-comparison projects were carried out (Graziani et al. 1998 Mosca et al. 1998). The purpose of this experiment was to evaluate the models ability to transport and disperse a tracer. 

When HI adds to a double bond, the proton acts as an electrophile, giving an intermediate carbocation that then reacts with the nucleophilic iodide ion to give the product. In the reaction of HI with 1-methylcyclohexene, there is only one product, 1-iodo-l-methylcyclohexane no l-iodo-2-methyl-cyclo-hexane is formed. 

Methyl-cyclo-hexane CH3—cyc/o-CfiHii 90.111.8 377.017.5 Derived from AfH in ref. 1986PED/NAY... 

The steric strain of the diaxial conformation is twice that of the axial conformation of methyl-cyclo-hexane or 2 X 7.6 = 15.2 kJ mole. However, interconversion of this conformation by a ring flip changes both axial methyl groups into equatorial methyl groups. The steric energy of this conformation is zero, like the equatorial conformation of methylcyclohexane. Thus, the diaxial conformation is 15.2 kJ mole" less stable than the diequatorial conformation. Because of this energy difference, approximately 99.5% of the compound exists in the diequatorial conformation at 25 °C. 

Mayer and co-workers have developed the coordination chemistry of tripodal-like ligands based on 1,3,5-trisub-stituted cyclohexane scaffolds. Typical ligands of this class are rfr,rfr-l,3,5-tris[(diphenylphosphanyl)methyl]-cyclo-hexane (tdppmcy) and rfr,rfr-l,3,5-tris(diphenylphosphino)cyclohexane (tdppcy). The reaction of tdppmcy with 1 in toluene gives trinuclear [ Ir(CO)Cl 3(tdppmcy)2] 79 with the tripodal ligand behaving as a trismonodentate ligand. Complex 79 was converted into trinuclear [ Ir(CO)(Cl)H 3(tdppmcy)2]3 80, [Ir(CO)(Cl)H2]3(tdppmcy)2 81, and [Ir(CO)H3]3(tdppmcy)2 82 by treatment with H, H2, and H , respectively." ... 

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