Cobalt-mediated, enantioselective synthesis of C(2) and C(1) dienes

The asymmetric C-H functionalization of norbornene and norbornadiene with five-, six-, and seven-membered cyclic enones mediated by the reactive intermediate [{η(5)-((t)BuMe(2)Si)C(5)H(4)}Co(NO)(2)] is reported. A novel base mixture derived from enantiopure ammonium salts and NaHMDS was used as a source of chirality, and this enantioselective desymmetrization of C(s) alkenes has been applied to the asymmetric synthesis of C(2)- and C(1)-symmetric diene ligands in high regioselectivity (3.7-20:1 anti/syn), near perfect diastereoselectivity (>99:1 dr), and high enantioselectivity (90-96% ee).     

The numerical integration of relative equilibrium solutions. The nonlinear Schrodinger equation

We analyse different error propagation mechanisms for conservativeand nonconservative time-integrators of nonlinear Schrödingerequations. We use a geometric approach based on interpretingwaves as relative equilibria.     

Direct lactonization of alkenols via osmium tetroxide-mediated oxidative cleavage

[reaction: see text] A highly efficient, mild, and simple protocol is presented for the tandem OsO(4)-mediated oxidative cleavage/oxidative lactonization of alkenols to lactones. The protocol couples the OsO(4)-catalyzed oxidative cleavage of olefins with Oxone as the co-oxidant with the direct oxidation of aldehydes in alcoholic solvents to their corresponding esters.     

2,4,6‐trichloropyrimidine. Reaction with anilines

The reaction of 2,4,6‐trichloropyrimidine 1 with a variety of 4‐substituted anilines 2 has been investigated. Monosubstitution occurs readily for all anilines except those containing strongly electron‐withdrawing groups. The yields of the isomeric products 3 and 4 parallel the Hammet constants of the ring substituents. The main product when ethanol was used as the solvent was the 4‐substituted‐2,6‐dichloropyrimidine 3. Spectral and X‐ray data confirmed this assignment. However, a solvent dependence on the 3:4 ratio was demonstrated. In some cases, excess aniline under forcing conditions led to 2,4‐disubstituted products.     

Silver-catalyzed enantioselective functionalizations of alkenes and alkynes: A short review

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Integral resource capacity planning for inpatient care services based on bed census predictions by hour

The design and operations of inpatient care facilities are typically largely historically shaped. A better match with the changing environment is often possible, and even inevitable due to the pressure on hospital budgets. Effectively organizing inpatient care requires simultaneous consideration of several interrelated planning issues. Also, coordination with upstream departments like the operating theatre and the emergency department is much-needed. We present a generic analytical approach to predict bed census on nursing wards by hour, as a function of the Master Surgical Schedule and arrival patterns of emergency patients. Along these predictions, insight is gained on the impact of strategic (ie, case mix, care unit size, care unit partitioning), tactical (ie, allocation of operating room time, misplacement rules), and operational decisions (ie, time of admission/discharge). The method is used in the Academic Medical Center Amsterdam as a decision-support tool in a complete redesign of the inpatient care operations.