Pol,,hedron Vol. 13. No. 13, cm. 2049-2054, 1994 Pergamon 0277-5387(94)JWO!WQ zyxwvutsrqponmlkjihgfedcbaZYXWVUTS SILYLATION COUPLED WITH DESILYLATION ROUTE TO NEWER SYNTHESES* KAMALENDU DEY? and KARTIK KUMAR NAND1 Department of Chemistry, University of Kalyani, Kalyani-741235, West and GEORGE B. KAUFFMAN ‘&evier Science Ltd Printed in Great Britain 0277-5387194 $7.00+0.00 AS A Bengal, India Department of Chemistry, California State University, Fresno, CA 93740, U.S.A. Abstract-Trimethylsilylation of the Schiff base bis(salicylaldehyde)propylene(Zhyd- roxy)diimine (abbreviated to H,salphd) and bis(orthohydroxyacetophenone)propylene(2- hydroxy)diimine (abbreviated to H,ohaphd) yielded trimethylsilylated ligands (Me,Si), salphd and (Me$i),ohaphd, respectively. These new silylated ligands smoothly reacted with VOCl, - 2H20, (7c-CSH,),TiC12 and (CH,),SnCl, to yield a new series of bimetallic oxovanadium(IV), organotitanium(IV) and organotin(lV) compounds. The reaction of [(n-CSHg)2Ti]2C1(salphd) (5), synthesized in this study, with Ph,C=NSiMe, is also described. The complexes have been characterized by elemental analyses, molar con- ductance values, magnetic susceptibilities, molecular weights and spectroscopic (UV- visible, IR, ‘H NMR, and ESR) data. Development of newer synthetic methods for coor- dination compounds is historically very significant and important as Alfred Werner himself carried out much pioneering and novel work in developing newer synthetic strategies for different types of coordination compounds. With this in view, we have initiated research in developing new synthetic routes for coordination compounds and organo- metallic compounds. The use of the formation and cleavage of carbon- elemental (C-E) bonds for synthetic purposes is well documented in the literature. Cleavage of bonds between transition or nontransition metals with other elements is also known to yield com- pounds which are otherwise very difficult to isolate. However, silylation of multidentate Schiff bases and other ligands and their use in complex for- mation are very rarely utilized. For the last several 2049 years we have been trying to develop new methods through this synthetic strategy for the preparation of new coordination, organometallic and organic compounds.‘-‘o The present paper describes some of our recently observed results on the silylation of the Schiff base H,salphd and H,ohaphd (Fig. 1) derived from the condensation of 1,3-diamino- propane-2-01 with salicylaldehyde and ortho- hydroxyacetophenone, respectively, and the reac- tions of the silylated Schiff bases, (Me,Si),salphd and (Me,Si),ohaphd with VOCl,. 2H20, (~c-C,H,)~ TiCl, and Me,SnCl,. Reaction of [(z-C,H& Ti12Cl(salphd) (S), synthesized in this study, with Ph,C==NSiMe, is also described. Materials *Based in part on a presentation at the Werner Cen- tennial Celebration Symposium, Spring ACS meeting, Denver, CO, 1993. TAuthor to whom correspondence should be addressed. All solvents were purified and dried according to standard procedures” before use. Manipulations were carried out under an atmosphere of nitrogen. Bis(cyclopentadienyl)titanium dichloride (Alfa Inorganic) was recrystallized from toluene. The EXPERIMENTAL