STRUCTURES AND RELATIONSHIP BETWEEN THE SN-119 NMR CHEMICAL-SHIFTS AND PK(A) OF THEIR PARENT ACIDS IN ORGANOTIN(I-DEL) CARBOXYLATES

Ten di-n-butyltin (I del) carboxylates [((Bu2SnOCOR)-Bu-n')(2)O](2) an d (Bu2Sn)-Bu-n(OCOR')(2) (R' = CCl3, CHCl2, CH2Cl, PhCH = CH, and 2,2, 3,3-tetramethylcyclopropyl) were synthesized and characterized by IR, H-1, C-13, Sn-119 NMR spectroscopy and elemental analysis. Together wi th other series of organotin(I del) carboxylates, their structural fea tures were discussed. The relationship between the Sn-119 NMR chemical shies in the organotin(IV) carboxylates [((Bu2SnOCOR)-Bu-n')(2)O](2), (Bu2Sn)-Bu-n(OCOR')(2), (Bu3SnOCOR)-Bu-n', Ph3SnOCOR' and the pK(a) v alues of their parent acids R'COOH was studied. The results have shown that the log[-delta(Sn-119)] of the same series of carboxylates is li nearly related to the pK(a) of R'COOH. It seems that the better is the linearity between the log[-delta(Sn-119)] and the pK(a), the more ana logous are the structures of the same series of carboxylates. (C) 1996 John Wiley & Sons, Inc.