Of phenyl groups

Phenyllithium can be used in Grignard-type reactions involving attachment of phenyl group, eg, in the preparation of analgesics and other chemotherapeutic agents (qv). It also may be used in metal—metal interconversion reactions leading, eg, to phenyl-substituted siUcon and tin organics. 

PMDI also contains isocyanates with higher molar masses (triisocyanates, tetraisocyanates, polyisocyanates), whereby the structure and the molar mass depend on the number of phenyl groups. This distribution influences, to a great extent, the reactivity, but also the usual properties like viscosity, flowing and wetting behavior as well as the penetration into the wood surface. 

Less reactive electrophilic reagents like those involved in acylation or alkylation apparently do not react with phenyl-substituted pyrylium salts the p-acylation of a phenyl group in position 3 of the pyrylium salt obtained on diacylation of allylbenzene (Section II, I), 3, a), and the p-l-butylation of phenyl groups in y-positions of pyrylium salts prepared by dehydrogenation of 1,5-diones by means of butyl cations (Section II, B, 2, f) probably occur in stages preceding the pyrylium ring closure. 

Phenyl iodide dissociates at Cu(110) to form a c(2 x 2) iodine layer, accompanied by coupling of phenyl groups which desorb as biphenyl but with evidence that some phenyl groups remain at the surface stabilised as chains at step-edges and on terraces as paired chains . Chemisorption of HC1 at Cu(110) is corrosive , with evidence for surface buckling. 

The decomposition of the peroxide IX, which gives acetophenone when the conditions are such as to favor the radical mechanism, gives methyl ethyl ketone if the reaction is run in acid. This is because of the superior migration aptitude of phenyl groups in real or incipient oxygen cations.112... 

Trimethylgermyl substituents in aromatic compounds are easily removed with halogen, yielding the corresponding aryl halide, as shown in reaction 8119. Another example of phenyl group displacement was carried out with bromine as in reaction 2 (see end of Table 2)64. 

Laser flash photolysis of phenylated Group 14 catenates followed by trapping of the radical intermediates indicates that homolytic cleavage of the metal-metal bond is the... 

The palladium-catalyzed arylation of 2-phenylphenols and naphthols shows an interesting feature of arylation of C-H bonds, leading to the formation of an (aryl)(aryloxy)palladium(n) intermediate.65,65a,65b The phenolates are suitable as precoordinating groups. The reaction of 2-hydroxybiphenyl with an excess of iodobenzene occurs regioselectively at the two ortho-positions of phenyl group under palladium catalysis (Equation (57)). In the case of 1-naphthol, the peri-position is phenylated (Equation (58)). 

Functionalization of polysilanes by chemical modification (post-polymerization) was covered in COMC II (1995) (chapter Organopolysilanes, p 101), where the formation of precursor polysilanes with potentially functionalizable side groups such as chloride, type 34 (via HCI/AICI3 chlorodephenylation of PMPS), 6 triflate, type 35 (via triflate replacement of phenyl groups)135,137 or alkyl halide (via chloromethylation of phenyl groups,138,139 type 36, or addition of HC1 or HBr to double bonds140) was discussed. Four other precursor polysilanes, which utilize the reactivity of the Si-Cl or Si-H bond, have been successfully applied in functionalization since COMC (1995) perchloropolysilane, 17 (see Section 3.11.4.2.2.(i) for synthesis),103 poly[methyl(H)silylene-f >-methylphenylsilylene],... 

Manipulation of the number of phenyl groups R1 to R3 on the rosaniline nucleus and their substitution pattern has proven a useful tool in producing a variety of commercially important derivatives. Currently, compounds with two (R1, R2 = C6H4CH3/C6H5 R3 = H) and especially three phenyl and/or toluene moieties (R1, R2, R3 = QH5/QH4CH3) are technically important. The CH3 groups are primarily located in m-position relative to the secondary amino group. 

---