Synthesis of a Masked Terminal Nickel(II) Sulfide via Reductive Deprotection and its Reaction with Nitrous Oxide

摘要

Addition of 1 equiv of KSCPh3 to [L^RNiCl] (L^R = {(2,6-ⁱPr2C6H3)NC(R)}2CH, R = Me, ^tBu) in C6H6 results in the formation of [L^RNi(SCPh3)] (>1, R = Me; >2, R = ^tBu) in good yields. Subsequent reduction of >1 and >2 with 2 equiv of KC8, in cold (-25 °C) Et2O, in the presence of 2 equiv of 18-crown-6, results in the formation of “masked” terminal Ni^II sulfides, [K(18-crown-6)][L^RNi(S)] (>3, R = Me; >4, R = ^tBu), also in good yields. An X-ray crystallographic analysis of these complexes suggests that they feature partial multiple bond character in their Ni-S linkages. Addition of N2O to a toluene solution of >4 provides [K(18-crown-6)][L^tBuNi(SN=NO)] (>6), which features the first example of a thiohyponitrite ([κ²-SN=NO]^2-) ligand.