The product of the reaction of D-ribono-1,4-lactone with benzaldehyde and concentrated HCl has been shown, by X-ray crystallography of its acetate, to be 3,4-O-(R)-benzylidene-D-ribono-1,5-lactone and not the 3,5-acetal as previously suggested; with ZnCl2 as catalyst the products are 2,3-O-(R)- and -(S)-benzylidene-D-ribono-1,4-lactone the former preponderating.
D -ribono-1,4-内酯与
苯甲醛和浓
盐酸的反应产物,通过其
乙酸盐的X-射线晶体学显示为3,4- O-(R)-亚苄基-D- ribono -1,
5-内酯,而不是以前建议的3,5-
乙缩醛;用ZnCl 2作为催化剂,产物是2,3- O-(R)-和-(S)-亚苄基-
D-核糖-1,4-内酯,前者占优势。