Benzene thermal reaction

Ti02 particles, the benzene-thermal reaction of TiCLi. and NaN3, chemical vapor reactions, plasma syntheses, or arc-melting [15-20], The optical properties of low-concentrated TiN nanoparticle systems were studied by Quinten [21], Highly dispersed TiN was used as an additive to improve the mechanical properties of titanium carbide-based cermets [22],... 

In another recent study, amorphous phosphorus nitride imide (HPN2), a ternary inorganic polymer, has also been prepared via a benzene-thermal reaction of PCI5 and NaN3 under mild conditions [40], The products have interesting morphologies (Fig. 10) of microtubes, hollow balls and square frameworks. Their potential use for industrial application is now under investigation. 

Nanocrystalline TiN of size 50 nm [72] and nanocrystalline ZrN of size 10-20 nm [73] were prepared through the benzene-thermal reaction with NaNs (Reaction (22)). 

The thermal decomposition of thia2ol-2-yl-carbonyl peroxide in benzene, bromobenzene, or cumene affords thiazole together with good yields of 2-arylthiazoles but negligible amounts of esters. Thiazol-4-ylcarbonyl peroxide gives fair yields of 4-arylthiazoles, but the phenyl ester is also a major product in benzene, indicating reactions of both thiazol-4-yl radicals and thiazol-4-carbonyloxy radicals. Thiazole-5-carbonyl peroxide gives... 

Whereas the cycloaddition of arylazirines with simple alkenes produces A -pyrrolines, a rearranged isomer can be formed when the alkene and the azirine moieties are suitably arranged in the same molecule. This type of intramolecular photocycloaddition was first detected using 2-vinyl-substituted azirines (75JA4682). Irradiation of azirine (54) in benzene afforded a 2,3-disubstituted pyrrole (55), while thermolysis gave a 2,5-disubstituted pyrrole (56). Photolysis of azirine (57) proceeded similarly and gave 1,2-diphenylimidazole (58) as the exclusive photoproduct. This stands in marked contrast to the thermal reaction of (57) which afforded 1,3-diphenylpyrazole (59) as the only product. 

Photochemical osmylation. The irradiation of the charge-transfer bands (Fig. 13) of the EDA complex of 0s04 with various benzenes, naphthalenes, anthracenes, and phenanthrene yields the same osmylated adducts as obtained in the thermal reactions. For example, irradiation of the purple solution of anthracene and 0s04 in dichloromethane at k > 480 nm yields the same 2 1 adduct (B) together with its syn isomer as the sole products, i.e.,... 

The generation of the benzoyloxyl radical relies on the thermal or photoinitiated decomposition [reaction (49)] of dibenzoyl peroxide (DBPO). An early study (Janzen et al., 1972) showed that the kinetics of the thermal reaction between DBPO and PBN in benzene to give PhCOO-PBN" could be followed by monitoring [PhCOO-PBN ] from 38°C and upwards. The reaction was first order in [DBPO] and zero order in [PBN], and the rate constants evaluated for the homolysis of the 0—0 bond in DBPO (k = 3.7 x 10-8 s-1 at 38°C) agreed well with those of other studies at higher temperatures. Thus in benzene the homolytic decomposition mechanism of DBPO seems to prevail. 

The origins of sonochemistry lie in the study of homogeneous systems and among the examples of early synthesis is the Curtius rearrangement which appeared in 1938 [34]. In this example benzazide gives nitrogen and phenyl isocyanate when sonicated in benzene (Eq. 3.1), and the rate is increased in comparison to the normal thermal reaction. This reaction was not fully investigated at the time and the observation that the reaction stopped after rapid initial steps was not explained. 

The reaction was also reported to occur thermally 4,4-dimethyl-2,3-diazabicyclo[3.2.0]hept-2-ene underwent nitrogen elimination to give 5,5-dimethylbicyclo[2.1.0]pentane (24) in benzene at 140°C.182 184 The kinetics of the reaction were measured. The mechanism of the thermal reaction of 5,5,6,6-tetrafluoro-2,3-diazabicyclo[3.2.0]hept-2-ene was also studied.185... 

Nickel(O) or palladium(II) compounds in stoichiometric amounts promote the ring enlargement of simple alkyl-substituted 1,2-divinylcyclobutanes in benzene at room temperature to give 1 1 metal complexes of cycloocta-1,5-dienes.119 Destruction of the palladium complexes with potassium cyanide affords the free cycloocta-1,5-dienes. The stereochemistry observed is the same as in the thermal reaction at 150°C. 

The hexasila-Dewar benzene 13 is thermally stable at —150 °C, but it gradually reverted to the hexasilaprismane 1243. The half-life is 11/2 = 0.52 min at 0 °C in 3-methylpentane. The activation parameters for the isomerization of 13 to 12 are a = 13.7 kcalmol-1, A= 13.2 kcalmol-1 and A= — 17.8 cal K-1 mol-1. The small Ea value is consistent with the high reactivity of Si=Si double bonds. Most probably, the small HOMO-LUMO gap of 13 makes it possible that the Si=Si double bonds undergo a formally symmetry forbidden [2 + 2] thermal reaction. Hexasila-Dewar benzene is a key... 

Cyclohexadiene reacted with the methoxyhydantoin in boiling benzene in the presence of trifluoroacetic acid to give the adducts (106) in 30-33% yield. The thermal reaction with p-chlorophenyl derivative gave (106a) in 75% yield. 

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