syn-Sesquinorbornatriene and its quadricyclane valence isomer

Synthesis of Selectively Labeled d-Fructose and d-Fructose Phosphate Analogues Locked in the Cyclic Furanose Form

“…The construction of the locked cyclic skeleton of the sugar analogues is described in Schemes −3. It is based on a key regio- and stereoselective cyclization step (yielding cyclic olefins 2 ), previously described by Martin et al Oxidation of the olefin functionality of 2 , yielding aldehyde 3 , was carried out by a variety of methods: ozonolysis under various conditions, , m -CPBA epoxidation followed by periodate oxidation, one-pot OsO 4 /HIO 4 oxidation, and two-step OsO 4 /4-methylmorpholine N -oxide and HIO 4 oxidation …”

“…Open olefin 1d: 72% yield; 1 H NMR δ 2.60 (d, J ) 6.5 Hz, 1H, OH), 3.39 (dd, J ) 9.4, 5.9 Hz, 1H, C7H2), 3.46 (dd, J ) 9.4, 6.3 Hz, 1H, C7H2), 3.77 (dd, J ) 7.1, 3.9 Hz, 1H, C4H), 3.85 (m, 1H, C6H), 3.86 (m, 1H, C5H), 4.05 (bdd, J ) 7.4, 3.9 Hz, 1H, C3H), 4.34 (d, J ) 11.9 Hz, 1H, Bn), 4.42 (d, J ) 12.0 Hz, 1H, Bn), 4.46 (d, J ) 12.0 Hz, 1H, Bn), 4.55 (d, J ) 11.3 Hz, 1H, Bn), 4.63 (d, J ) 11.9 Hz, 1H, Bn), 4.66 (d, J ) 11.3 Hz, 1H, Bn), 4.69 (d, J ) 11.3 Hz, 1H, Bn), 4.76 (d, J ) 11.3 Hz, 1H, Bn), 5.31 (ddd, J ) 10.6, 1.6, 1.0 Hz, 1H, C1H2), 5.31 (ddd, J ) 17.0, 1.6, 1.0 Hz, 1H, C1H2), 5.94 (ddd, J ) 17.0, 10.6, 7.4 Hz, 1H, C2H), 7. 20 Cyclization: Cyclic olefins 2a-d were prepared from the opened olefins 1a-d, respectively, as previously described 17,30 and purified by chromatography with ether/hexane 1:5. 2a: 47% yield; 1 H NMR δ 3.75 (dd, J ) 10.0, 6.2 Hz, 1H, C7H2), 3.80 (dd, J ) 10.0, 5.5 Hz, 1H, C7H2), 3.84 (dd, J ) 3.8, 1.6 Hz, 1H, C4H), 4.00 (dd, J ) 4.2, 1.6 Hz, 1H, C5H), 4.26 (ddd, J ) 6.2, 5.5, 4.2 Hz, 1H, C6H), 4.31 (ddt, J ) 7.4, 3.8, 1 Hz, 1H, C3H), 4.43 (d, J ) 12.0 Hz, 1H, Bn), 4.…”