A new series of unsaturated stannylenes is studied computationally. The singlet and triplet states of acyclic and cyclic stannylenes are fully optimized using the B3LYP, BHLYP, OPBE, and M06 functionals. The basis sets used are of double-ξ plus polarization quality with additional s- and p-type diffuse functions denoted DZP++. All cyclic and most acyclic stannylenes have been found to have triplet ground states. The most favored triplet state is that for the NHC (NMeCHCHNMe)SnSn: system, where the triplet state lies ∼20 kcal mol-1 below the singlet. The saturated cyclic systems are expected to be easier to synthesize, but the unsaturated cyclic counterparts have larger singlet-triplet splittings. A preparative outline based on retro-synthetic routes is briefly described.
Bibliographical noteFunding Information:
AB and PR acknowledge the facilities at the University of Mauritius. PPG would like to thank the United States National Science Foundation for financial support of this research under NSF grant CHE-1213696. HFS would like to acknowledge generous support from NSF grant CHE-1361178. HFS thanks the Alexander von Humboldt Foundation for allowing a scientific visit to LMU Munich, in the laboratory of Professor Christian Ochsenfeld. The authors are thankful to anonymous reviewers for their useful comments to improve the manuscript.
© 2016 The Royal Society of Chemistry.