The use of In(OTf)3 as a Lewis Acid in carbohydrate chemistry, and exploration in silicon tethered reactions

Abstract

The feasibility of using Indium (III) triflate as a Lewis Acid for a number of different carbohydrate reactions was explored. First, the use of In(OTf)3 as a catalyst in the acylation of a number of carbohydrates was explored. The utility and compatibility of the In(OTf)3 reaction conditions with a number of protecting groups on the sugars were examined by 1H NMR analysis. In the second part of the carbohydrate methodology, the feasibility of using In(OTf)3 to promote glycosylation reactions using a number of glycosyl donors was evaluated. These studies were conducted using 1H NMR, 13CNMR, and Micro-ToF mass spectrometry. In both cases, In(OTf)3 was found to be a viable if highly acidic Lewis acid for these reactions. Silicon tether methodology was explored with the goal of obtaining 1,3 and 1,2-amino alcohols. The parameters for this reaction were explored after precursors and 1,3-amino alcohols were synthesized. These studies were conducted using 1H NMR, 13C NMR, IR spectroscopy, and Micro-ToF mass spectrometry. While some success was achieved, this route is unlikely to be widely adopted due to the multi-step syntheses that are required to obtain viable reaction precursors.