Cyclohexane, as solvent

The thermochemistry of the ligand replacement reaction 10.10, where pip indicates piperidine, was investigated by Adamson s group, using cyclohexane as solvent [183]. 

Photolysis of l-methylnaphtho[l,8-de]triazine (32, R = Me) also results in extrusion of nitrogen and formation of a diradical intermediate (167). Thus, reaction in cyclohexane as solvent gives, among other products, bicyclohexyl and 1-methylaminonaphthalene, while 8-phenyl-1-methylaminonaphthalene is the only product formed when benzene is used as solvent. Photochemical decomposition of 32, R = Me, in the presence of olefins results in an unusual ring transformation, and with a-methylstyrene, for example, the triazine is converted into the dihydroazaphenalene derivative (168). When vinyl bromide and trans-... 

These conclusions were anticipated by product studies. Alkyl azides are readily available and their thermal and photochemical decomposition reactions have been studied. In general, light and heat induced decomposition of methyl azide does not produce a MeN species that can be intercepted in respectable yields with a bimolecular trap. For example, attempts to trap MeN with cyclohexane as solvent produced only a 0.4% yield of adduct. Photolysis of CH3N3 or CD3N3 at cryogenic temperatures fails to produce an IR spectrum attributable to triplet methylnitrene. The IR spectrum of CH2=NH (or CD2=ND) is observed instead. " ... 

Cyclohexane as solvent and Baker catalyst (all other cases, Johnson Matthey) were used. e4).5 ml of Et3N and AcOH were added, respectively. 

Even mote complex is the mixture of products which arises from the direct irradiation of benzotricy-clo[3.1.0.0 ]hex-3-ene (15), the di-ir-methane product of benzonorbomadiene (equation 12). In cyclohexane as solvent, 2-vinylindene and benzonorcaradiene are the major primary products (equation SS). ... 

Lithium dialkylamide having bulky alkyl groups, such as isopropyl groups, exhibits unique behavior in polymerization reactions of isoprene and divinylbenzene. It was previously reported by us that lithium dialkylamide underwent a stereospecific addition reaction with butadiene in the presence of an appropriate amount of dialkylamine in cyclohexane as solvent (1, 2). For instance, on reacting with butadiene, lithium diethylamide gave the sole adduct, 1-diethylamino-cis-butene-2, in a 98-997o purity. In the absence of free amine, on the other hand, no reaction took place under the same experimental conditions (50°C... 

Six variations for the R from methyl up to n-hexyl yielded strong C=C vibrations for the -fortn in the range of 1660-1659 cm". An accompanying weak absorption in cyclohexane as solvent between 1685 and 1675 cm was assigned to the Z-isomer. 

A property shared by all alkanes is their relative unreactivity. You will recall from Chapter 9 that the carbon-carbon and carbon-hydrogen bonds found in alkanes are nonpolar. Because alkanes don t have any polar bonds, they undergo only a small number of reactions and will dissolve only those organic compounds that are nonpolar or that have low polarity, such as oils and waxes. The nonpolar and low-reactive nature of alkanes makes them good organic solvents. Paints, paint removers, and cleaning solutions often contain hexane or cyclohexane as solvents. 

In his initial paper, Roth used acetic acid, methanol, and cyclohexane as solvents and Pd over carbon support, Pt/C, Pt, Pd/BaS04, and PtC>2 He settled on Pd/C and cyclohexane as optimal. Precision and agreement with Kistiakowsky s results were in the region of 0.1-0.2 kcal mol 1. 

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