ethyl chlorooximidoacetate 、
(2R,3R,4R,6E)-6-benzylidene-3,4-bis(phenylmethoxy)-2-(phenylmethoxymethyl)oxane 在
aluminum oxide 作用下,
反应 0.25h,
以42%的产率得到ethyl (4S,5S,7R,8R,9R)-4-phenyl-7,8-bis(phenylmethoxy)-9-(phenylmethoxymethyl)-1,10-dioxa-2-azaspiro[4.5]dec-2-ene-3-carboxylate