Why is thiol unexpectedly less reactive but more selective than alcohol in phenanthroline-catalyzed 1,2-- and -furanosylations?

The lack of catalytic stereoselective approaches for producing 1,2--furanosides emphasizes the critical need for further research in this area. Herein, we present a stereoselective -furanosylation method, utilizing a 4,7-dipiperidine-substituted phenanthroline catalyst. This developed protocol fills a gap in the field, enabling the coupling of cysteine residues and thiols with furanosyl bromide electrophiles.

Highly stereoselective synthesis of α-glycosylated carboxylic acids by phenanthroline catalysis.

Carbohydrate molecules with an α-glycosylated carboxylic acid motif provide access to biologically relevant chemical space but are difficult to synthesize with high selectivity. To address this challenge, we report a mild and operationally simple protocol to synthesize a wide range of functionally and structurally diverse α-glycosylated carboxylic acids in good yields with high diastereoselectivity. Although there is no apparent correlation between reaction conversion and p of carboxylic acids, we found that carboxylic acids with a p of 4-5 provide high selectivity while those of a p of 2.

Reducing the Cost of TD-CI Simulations of Strong Field Ionization.

Strong field ionization of molecules by intense laser pulses can be simulated by time-dependent configuration interaction (TD-CI) with a complex absorbing potential (CAP). Standard molecular basis sets need to be augmented with several sets of diffuse functions for effective interaction with the CAP. This dramatically increases the number of configurations and the cost of the TD-CI simulations as the size of the molecules increases.

Rare Events Sampling Methods for Quantum and Classical Ab Initio Molecular Dynamics.

We provide an approach to sample rare events during classical ab initio molecular dynamics and quantum wavepacket dynamics. For classical AIMD, a set of fictitious degrees of freedom are introduced that may harmonically interact with the electronic and nuclear degrees of freedom to steer the dynamics in a conservative fashion toward energetically forbidden regions. A similar approach when introduced for quantum wavepacket dynamics has the effect of biasing the trajectory of the wavepacket centroid toward the regions of the potential surface that are difficult to sample.