Thiourea-catalysed conjugate additions of amines to vinyl phosphonates and phosphinates.

Thiourea catalysts activated α,β-unsaturated phosphonates and phosphinates toward conjugate addition by amines to give β-aminophosphonates and β-aminophosphinates. The organocatalytic methodology was used to synthesise 15 β-aminophosphonates and -phosphinates in yields up to 99%. A gram-scale example furnished the corresponding β-aminophosphonate in an isolated yield of 99% with 97% catalyst recovery.

Accessing unsymmetrical Ru(II) bipyridine complexes: a versatile synthetic mechanism for fine tuning photophysical properties.

Three novel unsymmetrical Ru(II) bipyridine complexes were generated a convenient, modular, convergent synthetic route. An investigation of their photophysical properties revealed solvent-dependent excited state behaviour including altered absorption and emission wavelengths, emission lifetimes and quantum yields of phosphorescence.

Synthesis of Bis-heteroaryls Using Grignard Reagents and Pyridylsulfonium Salts.

Herein are reported ligand-coupling reactions of Grignard reagents with pyridylsulfonium salts. The method has wide functional group tolerance and enables the formation of bis-heterocycle linkages, including 2,4'-, 2,3'-, and 2,2'-bipyridines, as well as pyridines linked to pyrimidines, pyrazines, isoxazoles, and benzothiophenes. The methodology was successfully applied to the synthesis of the natural products caerulomycin A and E.

Synthesis of Pyridylsulfonium Salts and Their Application in the Formation of Functionalized Bipyridines.

An S-selective arylation of pyridylsulfides with good functional group tolerance was developed. To demonstrate synthetic utility, the resulting pyridylsulfonium salts were used in a scalable transition-metal-free coupling protocol, yielding functionalized bipyridines with extensive functional group tolerance. This modular methodology permits selective introduction of functional groups from commercially available pyridyl halides, furnishing symmetrical and unsymmetrical 2,2'- and 2,3'-bipyridines.