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Benzonitrile oxide and C,N-diphenylnitrone undergo highly regio-and face-selective cycloaddition reactions with levoglucosenone; in each case the major product results from approach anti to the 1,6-bridge of levoglucosenone, the oxygen of the 1,3-dipole becoming attached to the f3-carbon of the enone unit.Levoglucosenonet (1) is a chiral bicyclic D-glucose derivative prepared by pyrolysis of cellulose. Although its formation' and some aspects of its chemistry, such as its thermal stability,2 addition,3 and Diels-Alder reactions ,4 have been investigated in detail, its potential as a reactive dipolarophile has so far been neglected. We now report that it undergoes t Levoglucosenone = 1,6-An hydro-3,4-dideoxy-f3-~-glycero-hex-3enopyranos-2-ulose.

Reaction of deficient benzonitrile oxide (II) (obtained in situ by dehydrochlorination of benzohydroximoyl chloride) with (I) (models for 2,3‐unsaturated sugars) leads to monoadducts (III), (IV), (Va), and by‐products (VI) and (VII).