Synthesis and structures of [S&z.dbd;(H)P(μ-NR)]2, potential building blocks for inorganic phosphorus-sulfur macrocyclesElectronic supplementary information (ESI) available. CCDC 1062561-1062563. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5dt02069g

The reactions of the chloro-phosph( iii )azane dimers [ClP(μ-NR)] 2 with LiSH give the dimers [S&z.dbd;(H)P(μ-NR)] 2 ( III ), which are potential new building blocks for inorganic macrocycles of the type [{P(μ-NR)} 2 (μ-S)] n . NMR spectroscopic studies and DFT calculations show that the preference for the cis or trans isomers of III is largely influenced by the steric demands of the R-group, with cis isomers being preferred for bulky substituents. This is an important factor in regard to applications in macrocycle synthesis since the cis arrangement is pre-organized for cyclisation. Steric factors are the principle influence on the favourability of the cis and trans isomers of the novel dimers [S&z.dbd;(H)P(μ-NR)] 2 .