Stephen Roseblade

Iridium‐Catalyzed Chemoselective and Enantioselective Hydrogenation of (1‐Chloro‐1‐Alkenyl) Boronic Esters

Organoboron compounds play important roles in chemistry, especially in the field of organometallic catalysis where boronic acids, boronic esters, and trifluoroborates are invaluable for the construction of C O, C N, or C C bonds through various coupling reactions. a-Amino boronic acids, primarily obtained from (a-chloroalkyl) boronic esters, are a recent addition to this class of compounds, expanding them into completely new areas of use. They are a crucial structural element in a new class of anti-cancer peptide drugs. One member of this class of drugs, which contains a “borleucine” moiety, is marketed under the name bortezomib (Scheme 1).

Radical Cascade Processes Leading to Fused- and Spiro-Bicyclic Ring Systems

The course of the reaction of 2-propargyl-2-(2-carboethoxyvinyl)cyclohexanone with tributyltin hydride and AIBN either neat or in benzene solution is discussed. The structure of the spirocyclic major product is shown to differ from that previously suggested and plausible reaction pathways are presented to account for the outcome.