for the following products
2-Deoxy-2,2-difluoro-4,5-o-(1-methylethylidene)-D-erythro-pentonic acid ethyl ester | Ethyl (3RS)-2,2-difluoro-3-(2,2-dimethyldioxolan-4-yl)propionate and Ethyl (3R,S)-2,2-difluoro-3-hydroxy-3-(2,2-dimethyloxolan-4-yl)propionate
