The first general method for the palladium-catalyzed Suzuki-Miyaura and carbonyl enolate coupling of unactivated aryl arenesulfonates was developed utilizing XPhos, 1, and Pd(OAc)2. This is of significant interest because aryl tosylates and aryl benzenesulfonates are more easily handled and considerably less expensive than aryl triflates. This catalyst system effects the coupling of a variety of aryl, heteroaryl, and extremely hindered arylboronic acids with different aryl tosylates, under mild conditions. The same catalyst was employed in the first carbonyl enolate coupling of aryl arensulfonates.

In mammalian cells, the aurora kinases (aurora-A, -B, and -C) play essential roles in regulating cell division.

The dilithium salts of N,N′,N′′-tris(trimethylsilyl)diethylenetriamine (1), N-methyl-N′,N′′bis(trimethylsilyl)diethylenetriamine (2), and N-methyl-N′,N′′-bis(diisopropyl)diethylenetriamine (3) reacted in THF, at -40 °C, with AlCl 3 affording monomeric aluminum chloride derivatives 4 (55% yield), 5 (76% yield), and 6 (71% yield), respectively. Addition of 1 equiv of AlMe 3 to the amine 2 gave rise to the five-coordinate dimethylaluminum derivative 9 (67% yield); heating a toluene solution of 9 overnight at 80 °C induces a loss of methane giving rise to the four-coordinate methylaluminum compound 10 (50% yield). The amine 2 also reacted at low temperature with LiAlH 4 affording derivative 11 (38% yield). Compounds 4-6 reacted subsequently in toluene with 1 equiv of HCl and 1 equiv of AlCl 3 to afford the first chiral tetracoordinated aluminum cations 12 (94% yield), 13 (93% yield), and 14 (90% yield), respectively. Single-crystal X-ray diffraction studies of derivatives 4, 5, 8, 10, 11, 12, and 15 have been carried out. They revealed that the tridentate nitrogen donors enforce an approximately trigonal-monopyramidal coordination geometry for neutral and cationic four-coordinate aluminum complexes. All cationic aluminum derivatives 12-14 and the neutral aluminum chloride 4 brought about the oligomerization of propylene oxide (PO). Low molecular weight polymers having narrow molecular weight distributions were obtained. The 13 C NMR spectra of these polymers indicate that they consist exclusively of head-to-tail linkages and that these macromolecules are rich in meso diad and isotactic triad sequences. Due to the presence of a free axial site, a new mechanism for PO polymerization is proposed. Methyl-and hydridoaluminum derivatives 10 and 11, as well as aluminum alkoxide, prepared in situ by reacting derivative 13 with PO, initiated the polymerization of (D,L)-lactide in benzene at 80 °C. High molecular weight polymers of broad molecular weight distributions were obtained in good yields.

SNP does not decrease platelet activation during apheresis and subsequent storage, and only a minor proportion of activated (p-selectin+) platelets circulate after transfusion in men. Moreover, biotin labeling of PCs can safely be used in humans for the study of platelet recovery after transfusion, and measuring recovery at 1 hour may lead to an underestimation of the true recovery when activated platelets are transfused.