Oxonereg;; tetra(n-butyl)ammonium hydrogensulfate; (ethylenedinitrilo)tetraacetic acid disodium salt; sodium hydrogencarbonate; methyl 4,6-O-(R)-benzylidene-2-O-methyl-α-D-arabinohexopyranosid-3-ulose in ethylene glycol dimethyl ether; water T=0°C; pH=8; optical yield given as percent eeenantioselective reaction;

tributylphosphine; di-isopropyl azodicarboxylate in dichloromethane T=20°C; Mitsunobu cyclodehydration;

Oxonereg;; C6H10O6(C3H4)2; tetra(n-butyl)ammonium hydrogensulfate; (ethylenedinitrilo)tetraacetic acid disodium salt; sodium hydrogencarbonate in water; acetonitrile T=0°C; 2 h; other reaction time, solvent, reagent; Product distribution;

di-isopropyl azodicarboxylate; triphenylphosphine in dichloromethane T=20°C; Mitsunobu cyclodehydration; Title compound not separated from byproducts.;

1: 66 percent / magnesium / tetrahydrofuran / Heating 2: 72 percent / diisopropyl azodicarboxylate / CH2Cl2 / 20 °C 3: CH2Cl2 / 20 °C View Scheme

1: 66 percent / magnesium / tetrahydrofuran / Heating 2: 72 percent / diisopropyl azodicarboxylate / CH2Cl2 / 20 °C 3: CH2Cl2 / 20 °C View Scheme

nitrogen(II) oxide in dichloromethane T=20°C; 120 h;