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The Boehringer-Ingelheim phosphinoimidazoline (BIPI) ligands were applied to the formation of chiral quaternary centers in the asymmetric Heck reaction. Several different substrates were examined in detail, using more than 70 members of this new ligand class. Hammett relationships were determined through systematic variation of the ligand electronics. All substrates showed essentially the same Hammett behavior, where enantioselectivity increased as the ligands were made more electron-deficient. Ligand optimization has led to catalysts which give the highest enantioselectivities reported to date for these difficult systems.

Recent advances in combined HPLC/electrospray ionization-mass spectrometry provide effective new capabilities for the rapid characterization of oligonucleotides. Accurate mass measurements with errors < 0.3 Da, and determination of base and sugar modification and of nearest neighbor identities, can be routinely carried out on 10-100 component mixtures of RNA or DNA. These procedures are widely applicable in structural and analytical studies involving mixtures of oligonucleotides.

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The pilot-plant synthesis of nevirapine analogue 1 is described. The compound was prepared in eight steps from substituted pyridine raw materials and 4-hydroxyquinoline. The key transformation involves a novel one-pot conversion of an arylhalide to arylacetic acid under palladium catalysis, followed by regioselective reduction via in situ generated BH3/THF to the arylethanol intermediate 2. All stages were carried out on 10−150-kg scale.