Pentacoordinate Silicon Derivatives. III.¹ 2,2'2'-Nitrilotriphenol, a New Chelating Agent

Abstract

The copper-catalyzed condensation of 2-substituted iodobenzenes with 2-substituted anilines yielded the novel 2,2 ',2' '-trichloro-, trimethyl-, and trimethoxytriphenylamines. Cleavage of the trimethoxy species produced 2,2 ',2' '-nitrilotriphenol which was shown to be an effective chelating agent, reacting with a variety of silanes (ZSiX3) to form monomeric pentacoordinate derivatives, ZSi(OC6H4)3N; related aluminum and titanium chelates were also i_i prepared. The use of o-dianisidine in the above condensation yielded , , ',N '-tetrakis(2-methoxyphenyl)-3,3 'dimethoxybenzidine; cleavage afforded N,N,N',N'-tetrakis(2-hydroxyphenyl)-3,3'-dihydroxybenzidine, a hexaol from which a dimeric pentacoordinate silicon derivative was prepared.

Silatranes and Their Tricyclic Analogs

“…A standard synthesis of 1-organyltribenzosilatranes is the reaction of a trifunctional silane with tris(2-hydroxyphenyl)amine (equation 169) 402 .…”

“…The reaction of tris(2-hydroxyphenyl)amine with acetoxysilane may involve simultaneous nucleophilic attack at the silicon and electrophilic attack upon the leaving acetoxy group via a six-membered transition state. Similar reactions with alkoxy-or chlorosilanes are likely to occur via a disfavored four-membered strained transition state 402 3 73 Nevertheless, more accessible organyltrichlorosilanes are good reagents for the preparation of various organyltribenzosilatranes 403 , including o-substituted derivatives 404,405 . Tribenzosilatrane (167) having four alkyl chains was obtained in 52% yield from n-octyltrichlorosilane and tris(2-hydroxy-4-dodecylphenyl)amine by reaction 169 404,405 .…”

“…The reactions of tris(2-hydroxyphenyl)amine with trichloro-, trimethoxy-or triacetoxysilanes in boiling toluene afford the corresponding Si-substituted derivatives instead 24. Silatranes and their tricyclic analogs 1513 of 1-hydrotribenzosilatrane (equation 170) 402 . As evident from this reaction, the H Si bond of 1-hydrotribenzosilatrane is very sensitive to electrophilic attack.…”

“…Solvolysis of 1-chloro-or 1-acetoxytribenzosilatranes with methanol or phenol yields the methoxy or phenoxy derivatives (equation 172) 402 .…”

Structure of 2,2',2''-trimethoxytriphenylamine and 2,2',2''-trihydroxytriphenylammonium benzenesulfonate

“…2~2',2"-Trimethoxytriphenylamine [(I), Me3NTPH] and 2,2',2"-trihydroxytriphenylamine (H3NTPH) were obtained as described by Frye, Vincent & Hauschildt (1966). 2,2',2"-Trihydroxytriphenylammonium benzenesulfonate (II) was obtained from H3NTPH and benzenesulfonic acid in chloroform.…”