A New Synthesis of 1,3,4‐Trideoxy‐1,4‐iminoglycitols of Varying Chain Length by (C3 + Cn)‐Coupling of Allyl Halides with Glycononitrile Oxides

With the “correct” combination of 3- and 5-substituents and the appropriate catalyst the CN/NO hydrogenation of isoxazolines 1 proceeds with high stereoselectivity to yield hydroxypyrrolidines 2 with variable side chains in one step, by two-fold reduction and recyclization, as shown in the example in Equation (a).