[reaction: see text] Variations in the reagents and stoichiometries used to generate CuH in situ, as well as the nature of the ligands present, have led to a very efficient and inexpensive method for effecting hydrosilylations of dialkyl ketones.

A new class of hypervalent organobismuth compounds functionalized with coordinating pinacolborate esters of the nature ArBiCl 2 (2), Ar 3 Bi (3), ArPh 2 Bi (4), Ar 3 BiCl 2 (5), and ArPh 2 BiCl 2 (6), where Ar ) 3-fluoro-2-pinacolatoboronphenyl, have been prepared and structurally characterized. The Bi • • • O distance is between 2.58 and 3.47 Å in the solid state for all compounds, and reasonable bonding interactions are presumed to exist in compounds 2-4 and 6, where Bi • • • O < 3.0 Å. When ArPh 2 BiCl 2 ( 6) is exposed to CsF in the presence of furan, the [4 + 2] cycloaddition product of 3-fluorobenzyne + furan, 8, is isolated in 58% yield. Mechanistic evidence is offered to support the claim that 6 undergoes an unprecedented fluoride-promoted fragmentation to generate 3-fluorobenzyne, pinacol, BF 3 , and Ph 2 BiF.

No abstract

Pyridine derivatives R 0380 Lactams as Prostanoid Receptor Ligands. Part 4. 2-Piperidones as Selective EP 4 Receptor Agonists. -Compounds (VI) and (VIII) are reported to show the strongest target receptor-binding activity of all tested compounds. -(ELWORTHY*, T. R.; BRILL, E. R.; CAIRES, C. C.; KIM, W.; LACH, L. K.; TRACY, J. L.; CHIOU, S.-S.; Bioorg. Med. Chem. Lett. 15 (2005) 10, 2523-2526; Dep. Med. Chem., Roche Biosci., Palo Alto, CA 94304, USA; Eng.) -C. Oppel 38-150

Hydrosilylation Hydrosilylation O 0278 Tweaking Copper Hydride (CuH) for Synthetic Gain. A Practical, One-Pot Conversion of Dialkyl Ketones to Reduced Trialkylsilyl Ether Derivatives. -Variations in the reagents and stoichiometries used to generate CuH in situ, as well as the nature of the ligands present, lead to a very efficient method for hydrosilylations of dialkyl ketones resulting in their corresponding Tes and Tbs ethers. The method is competitive with the conventional two-pot approach involving metal hydride reduction followed by silyl halide/triflate protection. By control experiments the requirement for all three components (CuCl, base, and ligand) is ensured. -(LIPSHUTZ*, B. H.; CAIRES, C. C.; KUIPERS, P.; CHRISMAN, W.; Org. Lett. 5 (2003) 17, 3085-3088;