A Highly Stereoselective Synthesis of N-Alkyl(2-deoxy-β-D-arabino-hexopyranosyl)amines Via 2-Deoxyglycosyl Phosphorodithioates as Glycosyl Donors

Abstract

This work demonstrates a new application of 2-deoxy-α-D-glycosyl phosphorodithioates 1 as glycosyl donors in the synthesis of N-alkyl-(2-deoxy-D-arabino-hexopyranosyl)amines 3. The reaction of 1 with amines 2 proceeds with high β-stereoselectivity, at ambient temperature, in almost quantitative yield.     

Poly-Si films with low aluminum dopant containing by aluminum-induced crystallization

Typically, highly p-doped (2×10 18 cm -3 ) poly-Si films fabricated by the aluminum induced layer exchange (ALILE) process are not suitable for solar cell absorber layers. In this paper, the fabrication of high-quality, continuous polycrystalline silicon (poly-Si) films with lower doping concentrations (2×10 16 cm -3 ) using aluminum-induced crystallization (AIC) is reported. Secondary-ion-mass spectroscopy (SIMS) results showed that annealing at different temperature profiles leads to a variety of Al concentrations. Hall Effect measurements revealed that Al dopant concentration depends on the annealing temperature and temperature profile. Raman spectral analysis indicated that samples prepared via AIC contain some regions with small grains.