The aminolysis reactions involving primary amines with either Ti(iYX1ez)r or Ti(NEtz)a have been studied. The primary amines behave as bifunctional reactants, forming colored, insoluble, non-volatile bis-(primary amino)-titanium compounds Ti(;UR)z which (except for R = C6H5) are highly reactive toaards water or alcohols. L\-ith n-butylamii~e some soluble polymers of the general formula T~, ( N B U~)~~-~( S E~Z )~ were isolated. n'ith tert-butylamine the dimers Ti2(NB~~),2(NiLle2)~ and Ti2(NBut)z(SHBut)2(Nh1e2)2 were obtained. The structures of these polymeric metal-nitrogen compounds are discussed. ISTRODUCTIONIn a previous communication the preparation of a number of dialkylanlino derivatives of titanium and zirconium was reported (I). The titanium compounds (Ti?riRZ)( were monomeric and could be distilled in vacuo. The mononieric nature of these con~pounds was significant in view of the tendency of titanium to expand its coordination number and the presence of donor nitrogen atoms in the dialkyla~nino groups. The absence of coordination-polymerization in these compounds and the limitation of aminolysis (e.g.Ti(NIIez)a f 3HNEt2 -+ Ti(IKMe2)(NEt2)3 + 3HNh1ez) were ascribed t o steric hindrance.Since the steric effects of primary amines RNHz must be considerably less than those of secondary amines R2NH it was considered worthwhile to investigate the aminolysis of dialkylamino-titanium compounds with primary amines: Moreover, the primary amino derivatives were expected t o be polynleric since the primary nitrogen is potentially bifunctional and could lead t o the formation of a metal-R R N K nitrogen chain, M/ \M/ \AT. There was also the additional possibility that in the primary amino derivatives the titanium might be able to achieve a coordination number of six as a result of coordination-polymerization. We now report the results of the reactions of several primary amines with tetrakis-(dialky1amino)-titanium compounds. RESULTS AND DISCUSSIOKWhen either Ti(NR/Ie2)4 or Ti(NEt2)4 was treated with an excess of the primary amine RNH2, where R = Pr", Pri, Bui, Bus, cyclohexyl, or phenyl, the deeply colored insoluble bis-(monoalky1amino)-titanium compound Ti(iYR)2 was obtained (viz. equation [I]), with the primary amines being bifunctional. \With the exception of the anilino derivative, which was black and relatively stable towards hydrolysis, the new compounds were red and extremely vigorously hydrolyzed. The difference in chemical lPart I I I , D . C . Bradley and I . M . Thomas, Can.
A series of titanium(1V) halide -diamine complexes have been prepared and their infrared spectra measured in the solid state between 4 000 and 300 cnl-'. The configuration of the ligand and extent of aminolysis of the titanium-halide bond are discussed in relation to the spectra. Some assignments are proposed in the 600-300 cm-I region for the ethylenediamine complexes. INTRODUCTION An extensive study of the reaction between titaniuin(1V) halides and primary monoamines has shown that the primary arnines solvolyze the metal-halogen bond (1). By comparison, little is known of the reaction with primary diamines. Fowles and i\'IcGregor (2) reported an ethylenediainine (en) complex, TiCl2[HN(CH2)2NHz]z(en)z, and suggested that the ligands were chelated t o the metal. More recently Sumarokova and Sakenova (3, 4) claimed no aminolysis of the Ti-Cl bond occurred in the complexes TiC14.2en, TiC14. 3en, and TiC14.4en. However, there was evidence for aminolysis in the reaction with hexamethylenediarnine (HMD), and the compounds TiCl3[HN(CH2)6NH?1 .nHI\IID, where n = 1, 2, and 3, were reported (4). No spectroscopic examination of these compounds has been offered t o date. I n this paper we describe the preparation of a number of titanium(1V) halide -diarnine complexes including a series of 1 : 1 adducts. T h e infrared data for these compounds in the range 4 000 t o 300 cm-I is given in Table I. E X P E R I M E N T A L Materials and Manipz~lationSpecial precautions were taken to exclude water from the apparatus and chemicals, and all reactions were conducted in an atmosphere of dry nitrogen. The amines and solvents were dried by refluxing over sodium and then fractionally distilled. The titanium halides were distilled or sublimed into the reaction vessels immediately before use.The complexes were all prepared by the same general method. Solutions of the reactants in benzene were mixed in known molar ratios. Reaction was generally immediate and heat was evolved. The resulting mixture was stirred and occasionally heated for a period of time. The products, which were all insoluble, were filtered, washed with hot benzene, and dried in vacuo. All the products reacted vigorously with water and were hydrolyzed rapidly in air. The complexes were nonvolatile and insoluble in any solvent with which they did not react.The infrared spectra were all determined as mulls in Nujol and l~exachlorobutadiene-1,3 between NaCl or KRS-5 plates on a Beckman I.R. 10 grating instrument.Analyses were obtained as previously described ( 5 ) and the data is presented in Table 11. RESULTS A N D DISCUSSIONA number of questions remain to be answered with regard to the titaniurn(1V) halidediamine complexes so far reported in the literature: (a) the extent t o which arninolysis of the Ti-X bond (X = C1, Br, or I) occurs; (b) whether the diamine is acting as a chelate or as a trans bridging unit between two different metal atoms thus forming polymeric chains; and (c) a t what value of n in the chain HzN(CH2),NH2 would there be a possible change f...
New complexes of S4N4 with TiBr4, ZrCl4, NbCl5, and TaCl5 have been prepared. The infrared spectra of these complexes together with the spectra of previously reported complexes have been determined. Possible structures for the complexes are discussed.
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