Phenyl thermolysis

Anthranil, 7-nitro-synthesis, 6, 407 Anthranil, 3-phenyl-thermolysis, S, 91 Anthranilonitriles indazoles from, S, 274 Anthranils... 

Oxetane, 2-(o -chlorobenzyl)-2-phenyl-X-ray crystal structure, 7, 366 Oxetane, 3-chloromethyl-3-ethyl-ring strain, 7, 370-371 Oxetane, 2-(o-chlorophenyl)- H NMR, 7, 367 Oxetane, 2-cyano-synthesis, 7, 391-392 Oxetane, 2-cyano-3,3-dimethyl-2-phenyl-thermolysis, 7, 372 Oxetane, 2,2-dialkoxy-synthesis, 7, 396 Oxetane, 2,2-dialkyl-isomerization, 7, 377 Oxetane, 3,3-dialkyl-alkylative cleavage, 7, 381 polymers, 7, 382 Oxetane, 2-diethylamino-synthesis, 7, 390 Oxetane, 3,3-difluoro-molecular dimensions, 7, 365 Oxetane, 2,2-dimethyl-mass spectra, 7, 368-369 photolysis, 7, 373 synthesis, 7, 393 Oxetane, 2,3-dimethyl- H NMR, 7, 366 thermolysis, 7, 372 Oxetane, 2,4-dimethyl-mass spectrum, 7, 369... 

Oxetane, 2-ethoxy-3,3-dimethyl-2-phenyl-thermolysis, 7, 372 Oxetane, 3-fluoro-synthesis, 7, 390 Oxetane, 3-fluoro-3-nitro-synthesis, 7, 391 Oxetane, 3-iodo-synthesis, 7, 390... 

Isoxazole, 3-anilino-4-nitroso-5-phenyl-thermolysis, 6, 417 Isoxazole, 3-anilino-5-phenyl-brominalion, 6, 24 Isoxazole, 3-(p-anisyl)-5-phenyl-synthesis, 6, 63... 

Thermolysis of 4-methyl(4-phenyl)isoxazolin-5-one produced a-cyanophenylacetic acid <67JHC533). The pyrolysis of 3-methylisoxazoline-4,5-dione 4-oxime generated fulminic acid, which was trapped in a liquid N2 cooled condenser for further study. Pyrolysis of metal salts such as Ag or Na produced the corresponding highly explosive salts of fulminic acid 79AG503). Treatment of the oxime with amines generated bis-a,/3-oximinopropionamides (Scheme 65) <68AC(R)189). 

Acid treatment or thermolysis of aziridinyl phenyl ketone oxime generated a 2-isoxazoline (74JAP(K)74i 17462), while treatment of a diphenylcyclopropene (486) with NOCl generated a 2-isoxazoline in contrast to dialkylcyclopropene (487) which produced addition across the double bond (Scheme 126) (73MI41605). 

Isothiazole behaves as a typical stable aromatic molecule. Thermolysis of substituted isothiazoles at 590 °C leads to the formation of thioketenes (80MI41700) and phenyl-isothiazoles undergo photoisomerism (Section 4.17.6.2) (73BSF1743, 81T3627). 1,2-Benzisothiazole boils at 220 °C without appreciable decomposition, and the 2,1-isomer... 

Hofmann rearrangement, 4, 804 2-Thenoic acid phenyl ester photolysis, 4, 805 2-Thenoic acid, 5-phenyl-synthesis, 4, 868 2-Thenoyl peroxide thermolysis, 4, 804 Thenyl... 

Perfluorotetramethylthiadiphosphanorbornadiene and bis(trifluoromethyl) thiadiphosphole can be prepared by thermolysis of an adduct of methanol and hexakis(trifluoromethyl)-l,4-diphosphabarrelene with sulfur [113] (equation 23) Pyrolysis of the adduct of hexafluorinated Dewar benzene and phenyl azide results in ring expansion giving azepine, which photochemically yields an intramolecular 2-1-2 adduct, a good dienophile for the Diels-Alder reaction [114, //5] (equation 24) Thermolysis of fluonnated derivatives of 1,5-diazabicyclo-... 

In solution, the phenyl derivative 12.29 (R = Ph) is fluxional. The mechanism of the fluxional process has been shown by an N NMR investigation of a partially N-labelled sample, Le., PhCN2 N3S3 ( N = 99% N), to involve a series of 1,3-nitrogen shifts (Section 4.8.4). Thermolysis or photolysis of 12.29 generates the corresponding 1,2,3,5-dithiadiazolyl radicals [RCNaSa]". ... 

Pioneering studies have shown that the yield of iV-phenyl-3//-azepin-2-amine (32, R = Ph) from the thermolysis of phenyl azide in aniline increases as the ratio of azide to aniline decreases, and in dilute solution with an azide to aniline ratio of 1 200 a 54% yield of the 3//-azepine can be achieved.34 The reaction is successful with other arylamines, but the procedure is of limited preparative value as large volumes of amine are required and only moderate yields of 3H-azepines are obtained. 

The yield of 3//-azepine appears to be influenced by substituents on the azide ring although no in-depth study has been reported. 4-Halophenyl azides, in most cases, give rise to complex mixtures of products.177 4-Tolyl azide, on thermolysis in aniline, yields 5-methyl-iV-phenyl-3//-azepin-2-amine (18% mp 157-158°C), whereas the thermolyses of 4-methoxy-, 4-methyl-, 4-chloro-, and 4-nitrophenyl azides in a range of arylamines (4-chloro-, 4-methoxy-, and pen-tafluoroaniline) yield only azo compounds and uncharacterized tarry products.178... 

Likewise, thermolysis of 4-azidophenyl methyl ketone in methanol yields 5-acetyl-2-methoxy-3//-azepine (60%), compared to only an 8% yield from the photolytic reaction.78 119 The thermolysis of phenyl azide in refluxing cyclohexanol yields no 3H-azepine, only diphenyl-diazene (10%) and aniline (30%).74 In contrast, thermolysis of methyl 2-azidobenzoate in cyclohexanol furnishes a mixture of methyl 2-(cyclohexyloxy)-3//-azepine-3-carboxylate (20 % bp 127°C/0.1 Torr) and methyl 2-aminobenzoate (60%). Thermolysis of the azido ester in methanol under nitrogen in an autoclave at 150 C yields a 7 10 mixture (by 1HNMR spectroscopy) of the amino ester and methyl 2-methoxy-3//-azepine-3-carboxylate, which proved to be difficult to separate, and much tar.74 The acidic medium179 is probably responsible for the failure of methyl 2-azidoberjzoate to yield a 3//-azepine when thermolyzed in 3-methoxyphenol aniline (40%) is the major product.74... 

Photolysis of aryl azides in amine solution, with a tertiary amine as cosolvent to promote stabilization of the singlet nitrene, has met with some success. For example, the yield of 2-piperidino-3 W-azepme. obtained by the photolysis of phenyl azide in piperidine, is increased from 35 to 58% in the presence of A A /V. /V -tetramethylethylenediamine (TMLDA).180 Also, an improved yield (36 to 60 %) of A,(V-diethyl-3W-azepin-2-amine (38, R = Et) can be obtained by irradiating phenyl azide in triethylamine, rather than in dicthylaminc, solution.181 Photolysis (or thermolysis) of phenyl azide in TMEDA produces, in each case, 38 (R = Et) in 40% yield.181 In contrast, irradiation of phenyl azide in aniline with trimethylamine as cosolvent furnishes jV-phenyl-377-azepin-2-amine (32, R = Ph) in only low yield (2%).35... 

Singlet phenylnitrene, and hence /V,A -diethyl-3//-azcpin-2-amines, e. g. 102, can be generated by the thermolysis of A,-phenyl-Af,<9-bis(trimcthylsi]yl)hydroxylamine (100) in the presence of dialkylamines the reaction fails, however, with arylamines.210 Photofragmentation of the spiro oxaziridine 101 in diethylamine solution also produces the 3//-azepine 102,2,1 and an oxaziridine intermediate is probably involved in the formation, in low yield (1 %), of azepine 102 by the photolysis of A/,A( -diarylbenzoquinonc diimine A/,A/ -dioxides in benzene/die-thylamine solution.212... 

Thermolysis of the vinyl azide 11 in toluene furnishes a mixture of ethyl 2-phenyl-l//-3-benz-azepine-4-carboxylate(12), ethyl 4-(2-phenylvinyl)indole-2-carboxylate(13) and ethyl 1-benzyl-isoquinoline-3-carboxylate (14).82... 

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