Solphos: a new family of efficient biaryl diphosphine ligands.

Solphos (7,7'-bis(diarylphosphino)-3,3',4,4'-tetrahydro-4,4'-dimethyl-8,8'-bis-2H-1,4-benzoxazine) is a new modular atropisomeric biaryl ligand with a very attractive activity profile. A technically feasible synthesis is described allowing the synthesis of various derivatives of enantiopure ligand on a technical scale. Very good catalytic performances have been demonstrated for the following transformations: Ru-catalyzed hydrogenation of various beta-keto esters (95-99 % ee, s/c up to 100,000), of acetyl acetone (>99 % ee, dl/meso>98:2), and of an exocyclic alpha,beta-unsaturated acid (98.

New Applications of Polyfunctional Organometallic Compounds in Organic Synthesis Frequently used abbreviations are defined at the end of the article.

In the second half of the twentieth century much effort was invested in the preparation of highly reactive polar organometallic reagents. The high reactivity of these reagents precluded the presence of many functional groups and often good chemoselectivities and stereoselectivities could only by achieved by transmetalation reactions. The synthesis of increasingly complex target molecules and the desire to avoid tedious protection-deprotection steps has led inevitably to the use of functionalized organometallic reagents in retrosynthesis.