Rhodium-catalyzed regioselective olefin hydrophosphorylation.

Parameters influencing the selectivity of the (PPh(3))(3)RhCl-catalyzed hydrophosphorylation of olefins and enynes are described. The reaction between differentiated dienes was shown to be highly responsive to olefin substitution. The trimethylsilyl group effectively reversed the normal preference for hydrophosphorylation of an alkyne over an alkene. [reaction: see text]

Synthesis of cyclic peptides by ring-closing metathesis.

The synthesis of a series of "amide to amide" cyclized peptides by ring-closing metathesis (RCM) as well as a convenient synthesis for the linear precursors is described. In addition, the influence of the length of the alkene substituents and the influence of the peptide sequence is investigated, leading to a set of general rules to obtain "amide to amide" cyclized peptides by RCM.