Recoverable Phospha-Michael Additions Catalyzed by a 4-,-Dimethylaminopyridinium Saccharinate Salt or a Fluorous Long-Chained Pyridine: Two Types of Reusable Base Catalysts.

Phospha-Michael addition, which is the addition reaction of a phosphorus-based nucleophile to an acceptor-substituted unsaturated bond, certainly represents one of the most versatile and powerful tools for the formation of P-C bonds, since many different electrophiles and P nucleophiles can be combined with each other. This offers the possibility to access many diversely functionalized products. In this work, two kinds of basic pyridine-based organo-catalysts were used to efficiently catalyze phospha-Michael addition reactions, the 4-,-dimethylaminopyridinium saccharinate (DMAP·Hsac) salt and a fluorous long-chained pyridine (4--CHOCH-py, where = CF).

Side-chain conformations in the isomorphous polyfluorinated {4,4'-bis[(2,2-difluoroethoxy)methyl]-2,2'-bipyridine-κN,N'}dichloridopalladium and -platinum complexes.

The polyfluorinated title compounds, [MCl(CHFNO)] or [4,4'-(HCFCHOCH)-2,2'-bpy]MCl [M = Pd, (1), and M = Pt, (2)], have -C(H)OC(H)CFH side chains with H-atom donors at the α and β sites. The structures of (1) and (2) are isomorphous, with the nearly planar (bpy)MCl molecules stacked in columns. Within one column, π-dimer pairs alternate between a π-dimer pair reinforced with C-H.