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Benzoyl compounds structure

A general approach to rhenium hydrazido complexes is the reaction of oxo or chloro compounds with organohydrazines as has been demonstrated in an early report with the synthesis of [Re NNC(Ph)0 Cl2(PPh3)2] (310), " the molecular structure of which was solved in 1988. A detailed study on [Re(NNR)Cl2(PPh3)2] complexes with R = COPh or phthalazine shows that the course of subsequent reactions is governed both by the nature of the donor group R responsible for chelate closure and by the type of donor ligand introduced. No simple substitution chemistry has been observed for R = phthalazine. The benzoyl compound... [Pg.368]

Studies have been carried out on the alkylation of alkenes in the presence of SbFs, especially fluoroalkenes." For example, treatment of 1,1,1 -trifluoroethane with SbFs m the presence of tetraflu-oroethylene yields 90% of 1,1,1,2,2,3,3-heptafluorobutane. Perfluoroallyl or -benzoyl compounds with varying structures have also been utilized as alkyating agents (eqs 14 and 15)." - At elevated temperatures, intramolecular alkylation was observed in certain cases with perlluorodienes, forming perlluoro-cyclopentenes or perfluorocyclobutenes (eq 16)."... [Pg.31]

A certain compound A when treated with N bromosuccinimide and benzoyl peroxide under photochemical conditions in refluxing carbon tetrachloride gave 3 4 5 tnbromobenzyl bromide in excellent yield Deduce the structure of compound A... [Pg.469]

The structural studies of isoxazol-5-ones have shown that these compounds can be found in one of the three tautomeric forms (45-47 59,90,96-98 establishcd that the 3-methyl-4-benzoyl... [Pg.381]

Oxidation of ecgonine (2) by means of chromium trioxide was found to afford a keto acid (3). This was formulated as shown based on the fact that the compound undergoes ready themnal decarboxylation to tropinone (4)The latter had been obtained earlier from degradative studies in connection with the structural determination of atropine (5) and its structure established independently. Confirmation for the structure came from the finding that carbonation of the enolate of tropinone does in fact lead back to ecgonine. Reduction, esterification with methanol followed by benzoylation then affords cocaine. [Pg.5]

N-Benzoyl-Lalanine methyl ester is in turn about eight times more reactive than is its D enantiomer). The open-chain compounds may not bind to the enzyme in the same manner, however, as does the locked substrate. The conformation around the amido bond of the open-chain compounds, for example, can be transoid rather than cisoid (81). In addition, if equatorial 24 is considered to be the reactive conformer for both the Dand L enantiomers, and if the alanine methyl group is attracted to the hydrophobic aromatic binding subsite, then structures 34 and 38 would result. The L enantiomer of N-benzoyl-phenylalanine methyl ester 38 in this representation has approximately the same conformation as equatorial L-24. But attraction of the methyl of the D enantiomer to the location occupied by the methyl group of the L enantiomer causes the carbomethoxy group to move from the position it occupies in D-24. [Pg.401]

Most quinone reductions go through an intermediate radical or semiquinone stage, usually revealed by a one-electron step in the redox potential.100 The radical formed by the reduction of compound VI is especially stable, probably because of the additional involvement of the benzoyl group.101 The ordinary semiquinones are more stable in basic solution since some of the resonance structures of the neutral radical involve separation of charges. [Pg.52]

Brigl and Griiner45 reported the isolation of three products when 1,6-di-O-benzoyl-D-mannitol (29) was heated in boiling 1,1,2,2-tet-rachloroethane in the presence of p-toluenesulfonic acid as the catalyst. These compounds were assigned mono- and di-anhydro structures, and were later shown by Hockett and coworkers46,47 to be 1,4-anhydro-D-mannitol dibenzoate (30), l,4 3,6-dianhydro-D-man-nitol dibenzoate (31), and 2,5-anhydro-l,6-di-0-benzoyl-D-glucitol (32). The latter compound, which can be readily isolated from the... [Pg.120]

A number of optically active 1,1 -binaphthyl compounds, 8168 and 9,169 have been prepared with a view to use them as asymmetric catalysts. Compounds 8 (X = Br and OTf)170,171 and 9 [R3 = Me(OTf)2]169 have been used to resolve diols in their reaction with benzoyl chloride. Tin hydrides based on structure 8 (X2 = MeH,172 Bu H,173 and Me3CCH2H171) have been designed for carrying out enantioselective reductions. [Pg.824]

Benzoylation of D-g/ycero-D-gw/o-heptono-1,4-lactone with an excess of benzoyl chloride and pyridine afforded the hept-2-enono-1,4-lactone as the main product (198). The di- and triunsaturated compounds were isolated in very low yield from the mother liquors (199). Higher yields of the di- and triunsaturated derivatives 153 and 154 were obtained when the /5-elimination reaction was performed with triethylamine on the previously synthesized per-O-benzoyl D-g/ycero-D-gw/o-heptono-1,4-lactone. Employing 10% triethylamine in chloroform, the lactone 153 was obtained as an E, Z dias-tereomeric mixture in 9 11 ratio as determined by H n.m.r. When 20% triethylamine was used, the furanone 154 was obtained in 59% yield (200). Its structure was assigned, on the basis of H and 13C n.m.r. spectra, as 3 -benzoyloxy - (5Z)-[(Z)-3 - benzoyloxy - 2 - propenyliden] -2(5 H)- furanone. The stereochemistry of the exocyclic double bonds was established (201) by nuclear Overhauser effect spectroscopy (NOESY). [Pg.167]


See other pages where Benzoyl compounds structure is mentioned: [Pg.95]    [Pg.736]    [Pg.3]    [Pg.297]    [Pg.25]    [Pg.736]    [Pg.283]    [Pg.297]    [Pg.143]    [Pg.108]    [Pg.319]    [Pg.461]    [Pg.1058]    [Pg.122]    [Pg.84]    [Pg.38]    [Pg.227]    [Pg.200]    [Pg.138]    [Pg.152]    [Pg.119]    [Pg.185]    [Pg.400]    [Pg.408]    [Pg.212]    [Pg.269]    [Pg.161]    [Pg.108]    [Pg.205]    [Pg.241]    [Pg.265]    [Pg.267]    [Pg.270]    [Pg.312]    [Pg.172]    [Pg.593]    [Pg.617]    [Pg.43]   
See also in sourсe #XX -- [ Pg.30 , Pg.236 ]

See also in sourсe #XX -- [ Pg.236 ]




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Benzoyl compounds

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