STUDIES ON THE PROPERTIES OF SCHIFF BASE TYPE ARYLMERCURY COMPOUNDS Ⅲ TRANSMETALLATION REACTION OF SCHIFF BASE TYPE ARYLMERCURY COMPOUNDS WITH METALLIC TIN

The transmetallation reaction of 4 Schiff base type arylmercury compounds with metallic tin has been carried out in refluxing xylene.It was found that the reaction proceeds in the same manner as that of chloro[2-(phenylazo)phenyl]mercury(Ⅱ) to give dichlorobisaryltin(Ⅳ).The ~1H NMR spectra of the products provide evidence for the presence of N→Sn intramolecular coordination.The formation of dichlorobisaryltin(Ⅳ)as a unique product probably arises from the N→Sn intramolecular coordination which results in the increasing of the stability of the molecule.

STUDIES ON THE PROPERTIES OF SCHIFF BASE TYPE ARYLMERCURY COMPOUNDS.II ^(199)Hg NMR SPECTRA OF MERCURATED DERIVATIVES OF SUBSTITUTED BENZYLIDENEANILINES

^(199)Hg NHR spectra of 18 Schiff base type arylmercury compounds have been studied.It was further confirmed that in the molecule of XC_6H_4CH=NC_6H_3-2-HgC1-4-CH_3 there exists an intramolecular N→Hg coordination via a four-membered ring.For the series of XC_6H_4CH=NC_6H_3-2-HgCl-4-CH_3(X is a para-or mera-substituent),there is a good linear correlation between δ^(199)Hg and Hammett's o constants.The influence of substituents of C-pheny1 ring on the δ ^(199)Hg can be explained in terms of the intramolecular N→Hg coordination.

Synthesis and spectral properties of arylmercury derivatives of α-thiopicolinanilide

A series of thirteen arylmercury derivatives of α-thiopicolinanilide have been synthesized and characterized by elemental analysis,IR,~1H NMR and MS.The intramolecular coordination and the substituent effects on the MS and ^(199)Hg NMR behaviours have been studie6.It has been shown that a linear correlation exists between the ^(199)Hg chemical shifts and the Hammett-Brown constants σ^+,and the electron-donating groups cause the chemical shift to move upfield.

Synthesis of Symmetrical Biaryls via Rhodium Catalyzed Dimerization of Arylmercurials and Mechanism of the Dimerization

A series of symmetrical biaryls was synthesized from arylmercuric chlorides and biarylmercurials in the presence of [ClRh(CO) 2] 2 in hexamethylphosphoramide(HMPA). The mechanism of the [ClRh(CO) 2] 2 catalyzed dimerization of biarylmercurials was studied, and shown to be mainly intermolecular reaction.

Studies on the Properties of Schiff Base Type of Aryl mercury Compounds( Ⅰ )——~1H NMR Spectra of Some Schiff Base Type Aryl mercury Compounds and Substituted Benzyl ideneanilines

1H NMR spectra of 16 Schiff base type of arylmercury compounds and 4 -substituted benzylideneanilines have been studied. It was found that the p-substituents of the N-phenyl ring do not affect the δ values of methine proton, whereas the o-substitutents influence the δ values of methine proton, whereas the o-substituents influence the δ values of methine proton significantly. These changes can be reasonably interpreted in terms of the steric inhibition of o-substituents and intramolecular coordination of imino nitrogen with mercury. The influence of the m-or p-substituent of the C-phenyl ring on the δ values of methine proton exhibited a linear correlation with Hammett constants σp or σm. It was also confirmed that in the molecules of Schiff base type of arylmercury compounds there exists an intramolecular coordination via a four-membered ring.

Isokinetic correlation analysis of the series of electrophilic substitution reactions of o-substituted phenylmercurials

Isokinetic relationships of the series of electrophilic substitution reactions of o-substi- tuted phenylmercurials are studied, and the results show, for the first time, that isokinetic correlation analysis can reveal the dominant factor in the system of the reactions. The analysis of SE2 of o-substituted phenylmercuric chlorides indicates that the steric effect of o-substituents is the pre-dominant factor when I2 is used as electrophilic agent, however, the electronic effect of o-substituents would become the predominant factor when HCl is used as the electrophilic agent. In SE1 of o-substituted phenylmercuric chlorides, the results of the analysis display that the predomi-nant factor is the field effects of o-substituents. The determination of predominant factors in those reactions would provide further scientific basis for those reaction mechanisms.