Ab initio calculations on mono- and di-lithiated derivatives of thiourea predict that Li atom(s) will bridge N and S centres, leading to lengthening of the bond and shortening of one or both of the bonds in thiourea. The synthesised complex of dilithiated diphenylthiourea, [PhNPh)SLi·2HMPA]2 (1) displays many of the structural features suggested by theory, having been shown by X-ray crystallography to contain monomeric units with SLi and N(μ2Li)N bonds, these monomers then being linked by N: → Li coordinations.
- crystal structures
ARMSTRONG, D. R., Mulvey, R., BARR, D., SNAITH, R., WRIGHT, D. S., CLEGG, W., & HODGSON, S. M. (1989). Dilithiation of N,N′-diphenylthiourea, PhNHC(S)NHPh, in HMPA: the unexpected structure of the product, [PhNPh)SLi·2HMPA]2, and supporting ab initio MO calculations on model systems. Journal of Organometallic Chemistry, 362(1-2), C1-C4. https://doi.org/10.1016/0022-328X(89)85298-2