Synthesis of Various Cationic Ruthenium−Aqua Complexes with Hydrotris(3,5-diisopropylpyrazolyl)borate Ligand, Tpⁱ^PrRu(OH₂)<i>_n</i>(L)₃_-<i>_n</i>·(CF₃SO₃)(THF)<i>_x</i>, and Their Structures Supported by Hydrogen-Bonding Networks¹

Abstract

The labile cationic aqua complex, Tp iPr Ru(OH 2 ) 2 (THF)·(OTf)(THF) 2, 2, containing the hydrotris(3,5-diisopropylpyrazolyl)borate ligand (Tp i Pr ), is prepared by protonolysis of the ruthenium pentahydride complex Tp iPr RuH 5, 1, with trifluoromethanesulfonic acid (TfOH) in THF. Treatment of 2 with various 2e and 4e donors results in displacement of the THF and aqua ligands to give Tp iPr Ru(OH 2 ) n (L) 3 - n ·(OTf)(THF) x, 3 − 6 (L= py, bipy, phen, pz iPr -H, PPh 3, dppe, MeCN, t BuCN, C C(H)Ph; n = 0−2), and thus, complex 2 serves as a versatile precursor for a variety of cationic ruthenium aqua complexes. X-ray crystallographic analysis of the di- ( 2, 3b, c ) and monoaqua complexes ( 4c, 5 ) reveals ternary hydrogen-bonding networks among the aqua, OTf -, and THF fragments.