Influence of the Homopolar Dihydrogen Bonding CH⋅⋅⋅HC on Coordination Geometry: Experimental and Theoretical Studies

The reaction of the N‐thiophosphorylated thiourea (HOCH 2 )(Me) 2 CNHC(S)NHP(S)(O i Pr) 2 (HL), deprotonated by the thiophosphorylamide group, with NiCl 2 leads to green needles of the pseudotetrahedral complex [Ni(L‐1,5‐ S , S′ ) 2 ] ⋅ 0.5 ( n ‐C 6 H 14 ) or pale green blocks of the trans square‐planar complex trans ‐[Ni(L‐1,5‐ S , S′ ) 2 ]. The former complex is stabilized by homopolar dihydrogen CH⋅⋅⋅HC interactions formed by n ‐hexane solvent molecules with the [Ni(L‐1,5‐ S , S′ ) 2 ] unit. Furthermore, the dispersion‐dominated CH⋅⋅⋅ HC interactions are, together with other noncovalent interactions (CH⋅⋅⋅N, CH⋅⋅⋅Ni, CH⋅⋅⋅S), responsible for pseudotetrahedral coordination around the Ni II center in [Ni( L ‐1,5‐ S , S′ ) 2 ] ⋅ 0.5 ( n ‐C 6 H 14 ).