Synthesis and Reversible Control of the Fluorescent Properties of a Divalent Tin Dipyrromethene

摘要

Stannylenes are heavy congeners of carbenes and have been widely investigated. They easily dimerize without steric protection, and bulky substituents are necessary to stabilize these species. An alternative strategy for stabilization is the utilization of intramolecular coordination by the introduction of anionic chelating ligands such as β-diketiminate, aminotroponiminate, or amidinate. By the introduction of these ligands, LSnCl-type compounds have been isolated. Chloride is the reactive ligand and is easily replaced by other small, reactive ligands, such as alkoxide, amide, azide, triflate, and hydride. The presence of these small, reactive ligands promotes valuable reactivities, such as the polymerization of lactide, the cyclization of isocyanate, and the hydrostannylation of carbon dioxide.