Ring synthesis 1,3-diphenyl

Because of the ease of ring synthesis, symmetrically trisubstituted s-triazines have been more thoroughly studied, but a few nucleophilic substitutions of derivatives bearing a single leaving group are known. 2-Chloro-4,6-diphenyl- and 2-chloro-4,6-dimethyl-s-triazines (318) undergo facile nucleophilic displacements with ammonia, amines, and hydrazine, with alkoxide, or with hydrosulfide... 

Ring Synthesis and Destruction.—One method of preparing thiophens is by inserting a sulphur atom into an acyclic precursor. The sulphur-transfer reagent may be a simple inorganic compound, as illustrated by the formation of (11) from ethyl phenyl ketone (10) on treatment with pyridine and thionyl chloride. The simplest sulphur-transfer reagent is elemental sulphur, as in the production of the thiophen (13 X = S) from l,4-diphenyl-2,3-dibenzylbutadiene (12). The reaction of (12) with selenium dioxide affords the corresponding selenophen (13 X = Se). ... 

A 10-20%-soln. of the startg. m. (mixture of cis- and rrawj-isomers) in diphenyl-methane heated at 280-300° in a Pyrex ampoule methyl 3-methyl-2-butenoate. Y 90%.-In combination with photochemical oxetane ring synthesis from ethylene derivs. and oxo compds. (s. Synth. Meth. 19, 764), ethylene deriv.-oxo compd. interconversion may be achieved. F. e. s. G. Jones II, S. B. Schwartz, and M. T. Marton, Chem. Commun. 1973, 374. 

The structure of grayanic acid (351) has been confirmed by synthesis 101). It co-occurs with the ring-opened diphenyl ether congrayanic acid (352) in the lichen Gymnoderma melacarpum 47). Interestingly the dibenzo-furan melacarpic acid (353), a product of carbon-carbon oxidative coupling, also occurs in this lichen. 

The cyclized products 393 can be prepared by the intramolecular coupling of diphenyl ether or diphenylamine(333,334]. The reaction has been applied to the synthesis of an alkaloid 394[335]. The intramolecular coupling of benzoyl-A-methylindole affords 5-methyl-5,10-dihydroindenol[l,2-b]indol-10-one (395) in 60% yield in AcOH[336]. Staurosporine aglycone (396) was prepared by the intramolecular coupling of an indole ring[337]. 

Aziridine, 2,3-diphenyl-l-(2,4,6-trinitrophenyl)-irradiation, 7, 61 Aziridine, 1,2-divinyl-rearrangement, 7, 539 Aziridine, 2,3-divinyl-rearrangement, 7, 42, 65, 539 Aziridine, N-ethyl-inversion, 7, 6 Aziridine, 2-halo-reactions, 7, 74 Aziridine, A/-halo-invertomers, 7, 6 Aziridine, 2-methyl- N NMR, 7, 11 Aziridine, methylene-ring-ring valence isomerizations, 7, 22 synthesis, 7, 92 Aziridine, iV-nitroso-reactions, 7, 74 Aziridine, iV-phosphino-inversion, 7, 7 Aziridine, 1-phthalimido-UV irradiation, 7, 62-63 Aziridine, l-(3-thienyl)-2-vinyl-rearrangement, 4, 746 Aziridine, 7V-trimethylsilyl-inversion, 7, 7 Aziridine, 1,2,3-triphenyl-irradiation, 7, 61 Aziridine, vinyl-isomerization, S, 287 Aziridinecarboxylic acid ring expansion, 7, 262 Aziridine-2,2-dicarboxylic acid, 1-methoxy-diethyl ester... 

Benzo[b]furan, 3-(2-hydroxy-3,5-dichlorophenyl)-5,7-dichloro-properties, 4, 708 Benzo[b]furan, 2-lithio-synthesis, 4, 652 Benzo[i]furan, 3-lithio-ring opening, 4, 79 Benzo[b]furan, methoxy-mass spectrometry, 4, 583 Benzo[b]furan, 6-methoxy-2,3-diphenyl-synthesis, 4, 679... 

Benzo[6]thiophene, 2,3-dimethyltetrahydro-oxidative ring opening, 4, 768 Benzo[6]thiophene, 2,3-diphenyl-synthesis, 4, 109 Benzo[b]thiophene, 2-ethyl-synthesis, 4, 915 Benzo[6]thiophene, 2-fluoro-synthesis, 4, 932... 

Benzo[c]thiophene, 1,3-diphenyl-oxidative ring opening, 4, 768 synthesis, 4, 141-142... 

Furazano[3,4-/]quinoxaline, 7,8-diphenyl-synthesis, 6, 412 Furazanothiophene synthesis, 6, 417 Furazans, 6, 393-426 biological activity, 6, 425 bond angles, 6, 396 bond lengths, 6, 396 coordination compounds, 6, 403 diamagnetic susceptibilities, 6, 395 dipole moments, 6, 395, 400 heats of combustion, 6, 400 heterocyclic ring reactions, 6, 400-403 IR spectra, 6, 398 isoxazoles from, 6, 81 mass spectra, 6, 399 microwave spectroscopy, 6, 395, 396 MO calculations, 6, 395 monosubstituted... 

Imidazolium halides pyrolysis, 5, 449 Imidazolium ions acylation, 5, 402 H NMR, 5, 352 hydrogen exchange, 5, 417 nucleophilic attack, 5, 375 reactivity, 5, 375 ring opening, S, 375 Imidazolium oxides in pyrrole synthesis, 4, 344 Imidazolium perchlorate, 1,3-diphenyl-acylation, 5, 402 Imidazolium salts 1-acetyl-... 

The procedure described is essentially that of Shioiri and Yamada. Diphenyl phosphorazidate is a useful and versatile reagent in organic synthesis. It has been used for racemlzatlon-free peptide syntheses, thiol ester synthesis, a modified Curtius reaction, an esterification of a-substituted carboxylic acld, formation of diketoplperazines, alkyl azide synthesis, phosphorylation of alcohols and amines,and polymerization of amino acids and peptides. - Furthermore, diphenyl phosphorazidate acts as a nitrene source and as a 1,3-dipole.An example in the ring contraction of cyclic ketones to form cycloalkanecarboxylic acids is presented in the next procedure, this volume. 

With the synthesis of the benzylidene hydrazones of selenazoles, it was possible to prepare formazans containing a selenazole ring. Of the compounds already described (Section I,C,1), 2-benzylidene-hydrazino-4,5-diphenyl- and 2-benzylidenehydrazino-4-methyl-5-carb-ethoxy-selenazole were used to couple with diazonium salts in order... 

The 2-(2-pheriylvinyl) derivative 18 and the thienyl compound 20 cyclize exclusively at the alkene carbon, and at the thiophene ring, to give 3,4-diphenyl-l//-2-benzazepine (19) and 4-phenyl-6-//-thieno[3,2-e]-2-benzazepine (21), respectively.48 A mechanistic rationale for these results has been offered. This method has been extended to the synthesis of 7Z7-pyrido[3,4-t/]-, 7//-pyrido[2,3-t/]- and 77/-pyrido[4,3-r/]benzazepincs and to other thieno- and furo-fused 2-benzazepines.244... 

The Suzuki reaction97 allows tire coupling of two aromatic rings by reaction of an arylboronic compound with a iodo or bromo aryl derivative. The tetrakis (U iphenylphosphine) Pd is the catalyst working in the basic medium. This reaction was recently used98 in aqueous media for the preparation of different isomers of diphenyldicarboxylic acids (Fig. 5.21) but also for the synthesis of soluble rodlike polyimides99 by coupling the 3,6-diphenyl- V, V,-bis(4-bromo-... 

An alternative synthesis of a thermally stable cyclopentadienyl functionalized polymer involved ring bromination of poly(oxy-2,6-diphenyl-l,4-phenylene), followed by lithiation with butyl lithium to produce an aryllithium polymer. Arylation of 2-norbornen-7-one with the metalated polymer yielded the corresponding 2-norbornen-7-ol derivative. Conversion of the 7-ol to 7-chloro followed by treatment with butyl lithium generated the benzyl anion which undergoes a retro Diels-Alder reaction with the evolution of ethylene to produce the desired aryl cyclopentadiene polymer, 6. 

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