反应详情

It was surprising that the process of Niedballa and Vorbruggen formed the β-anomer to the near exclusion of the α-anomer only in the examples wherein deoxyribose and arabinose were utilized (DE 1 919 307, Examples 3 and 14). However, such results were not at all surprising where ribose or glucose was employed, because it is known that 2′-ester derivatives of ribose normally form the β-anomer in preference to the α-anomer product. Noteworthy is that where a predominance of β-anomeric product was formed from deoxyribose and/or arabinose as starting materials. Only low percent yields of product were obtained (DE 1 919 307 at Example 3, 20.5% yield from a deoxyribose starting material, and Example 14, 27.2% yield from an arabinose starting material).

1. customHowever, such results
2. customnormally form the β-anomer in preference to the α-anomer product