Dephenylation

Plumbyl halides with a lead-manganese bond have been prepared by the following dephenylation or demethylation reactions191 ... 

Bis(tributyltin)oxide in antifouling paint was found to change to tributyltin chloride and an unknown organotin species by Allen and coworkers106. The organotin species appear to be held strongly within the paint film. In the case of triphenyltin chloride and triphenyltin acetate, evidence of dephenylation to form diphenyltin and monophenyltin compounds has been obtained. 

Methadone Methadone, 6-dimethylamino-4,4-dephenyl-3-heptanone (3.1.37), is synthesized by alkylation of diphenylacetonitrile using l-dimethylamino-2-propylchloride in the... 

Let us assume that the 2- and 3-dephenylation reactions to form the parent heterocycle isoxazolidine have the same enthalpies as those of isopropylbenzene and dimethylani-line, 108.7 and 118.6 kJmol , respectively. Therefore, the enthalpy of formation of isoxazolidine is predicted to be ca 6 kJmoL. Consider the reaction in eqnation 13. 

Conyza canadensis (L.) Cronq. Xiao Fei Peng (aerial part) Essential oils, matricaria ester, dehydromatricaria ester, linoleyl acetate, limonene, linalool, centaur X, dephenyl methane-2-carboxylic acid, cumulene, O-benzylbezoic acid.48 Relieve swelling, itchiness, treat intestine and liver infection, a detoxicant, externally for skin eczyma, wounds, pain caused by arthrritis, toothache. 

This public health statement tells you about polybrominated biphenyls (PBBs) and polybrominated dephenyl ethers (PBDEs) and the effects of exposure. 

Another route to cyclohexasilane rings with silanyl side chains begins with cyclosilanylpotassium and chlorosilanes Ph Me3 SiCl (Scheme 15). Dephenylation of the resulting silyl-substituted cyclohexasilanes with triflic acid and subsequent reduction... 

Thus, the action of sulfuric acid on 1,1-diphenyltetramethyldisilane below 10° C followed by treatment with ammonium chloride gives 1,1-dichlorotetramethyldisilane in 60% yield (116). Similarly, dephenylation by sulfuric acid of 1,2-diphenyl-1,2-dimethyl-1,2-disilacycloheptane gives, after treatment with ammonium hydrogen fluoride, 1,2-difluoro-1,2-dimethyl-1,2-disilacycloheptane in 81% yield (112, 124), whereas this product can not advantageously be obtained from the 1,1,2,2-tetramethyl compound (see Section III, C,4). 

On the other hand, chlorodephenylation in benzene solution affords completely dephenylated products. Thus, 1,1-dichlorotetramethyldisilane and 1,1,1-trichlorotrimethyldisilane are obtained from the corresponding phenyldisilanes (116). 

Haglund, P., Zook, D.R., Buser, H.-R., Hu, J., 1997. Identification and quantification of polybrominated dephenyl ethers and methoxy-polybrominated diphenyl ethers in Baltic biota. Environ. Sci. Technol. 31, 3281-3287. 

Chiral polymethacrylate[poly(dephenyl-2-pyridylmethyl-methacrylate] [157,158]... 

The reactions of sulfonium salts with organometallic reagents probably involve five-coordinate sulfur species. For example, dephenylation of triphenyl-sulfonium tetrafluoroborate (37) with vinyllithium and the stereospecific... 

The formation of unsubstituted quinoxaline 1,4-dioxide in the Beirut reaction has been observed using a number of substrates benzoylacetalde-hyde and its enamines,395 vinyl acetate (Et2NH),396 acetylene (NEt3)397,398 propargyl alcohol, propiolic acid, and phenylacetylene (various amines).398 Some of these are unexceptional, but the apparent dephenylation in the case of the phenylacetylene is surprising. However, recently the reaction of benzofuroxan with diethylamine was reinvestigated399 (see Section V,E), and quinoxaline dioxide was found to be one of the major products from a complex sequence of oxidation and reduction reactions. It seems probable with phenylacetylene, and possible in other cases too, that the amines play more than a catalytic role in quinoxaline dioxide production. The amino-quinoxalinone 175 was reported, using vinyl acetate and morpholine.396... 

Figure 4 (a) in situ IR spectra of DMPD synthesis at 0.101 MPa and 403 K with dephenyl phosphinic acid catalyst, (b) The variation of methanol and intermediates IR intensity and DMC/DMPD concentration vs. time. 

Reduction of [(Ph3P)Pt(OAc)2]2 with formic acid accompanied by dephenylation affords complexes with Ph2P and PhP ligands ... 

Dephenylation of phosphine-borane complexes. A P-phenylphospholane-borane complex is converted to the P-lithio reagent by treatment with lithium. The latter species are used for the synthesis of chiral ligands. 

When in water, gives transitional forms diphenyl-arsenious acid and dephenyl-arsyne oxide, also toxic. 

Hydrolyzes with formation of water soluble salts of dephenyl-arsenious acids. 

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