We herein report a general, practical, and highly efficient method for asymmetric synthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantio­selectivity and stereo­specificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method signifies the generality of diboron-enabled [3,3]-sigma­tropic rearrangement.

The nonlinear optical activity of bacteriorhodopsin (bR) Langmuir-Blodgett (LB) films were investigated computationally and experimentally. The second harmonic generation optical rotary dispersion (SHG-ORD) response was calculated directly from the known structure and orientation of the PSB retinal chromophore within bR with no adjustable parameters. The predicted results agree remarkably well in sign, magnitude, and trend with the experimental SHG-ORD measurements. The calculations indicated negligible chirality with the tensor for the PSB retinal chromophore, but significant chiral-specific activity for the thin film through a relatively simple orientational mechanism.

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Three different b-cyclodextrins, peracylated on the primary hydroxymethyl rim of the cyclodextrin (6-C n ) 7 b-CD, and nine different nitrilotriacetic acid-modified inclusion ligands (R-NTA) have been prepared and their self-assembly properties characterized. These modular amphiphiles have been developed to promote twodimensional crystallization of proteins at the lipid-water interface. Pressure-area isotherm data suggest that the occupancy of the host sites within the (6-C n ) 7 b-CD monolayers vary as a function of the known host-guest binding constant for the unmodified b-CD host and R guest substituents. Negative-stain TEM experiments show that vesicles are formed upon mild sonication of (6-C 10 ) 7 b-CD and (6-C 16 ) 7 b-CD in 10 mM Tris, pH 7.4 buffer. These results indicate that (6-C n ) 7 b-CD forms stable lyotropic phases that may be useful for templating the interfacial crystallization of histidine-tagged proteins or other molecules capable of interacting with the R-NTA guest ligands.