1: 96.5 percent / 30percent aq. H2O2, pyridine / CH2Cl2 / Ambient temperature 2: 90 percent / TBAF / tetrahydrofuran / Ambient temperature View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: 1) hexamethyldisilazane (HMDS), ammonium sulfate, 2) trimethylsilyl triflate (TMSOTf) / 1) reflux, 1 h, 2) 1,2-dichloroethane, a) -22 deg C, 15 min, b) room temperature, 0.5 h<br />2: 85.5 percent / methanol; H₂O / 18 h / 85 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 6 steps<br /> </b>1: 1) lithium hexamethyldisilazide / 1) THF, -78 deg C, 1h, 2) room temperature, 30 min<br />2: tetrahydrofuran / -78 &deg;C<br />3: DIBAL-H / toluene / 2 h / -78 &deg;C<br />4: 96 percent / pyridine, DMAP / CH₂Cl₂ / 2 h / 0 &deg;C<br />5: 1) hexamethyldisilazane (HMDS), ammonium sulfate, 2) trimethylsilyl triflate (TMSOTf) / 1) reflux, 1 h, 2) 1,2-dichloroethane, a) -22 deg C, 15 min, b) room temperature, 0.5 h<br />6: 85.5 percent / methanol; H₂O / 18 h / 85 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: DIBAL-H / toluene / 2 h / -78 &deg;C<br />2: 96 percent / pyridine, DMAP / CH₂Cl₂ / 2 h / 0 &deg;C<br />3: 1) hexamethyldisilazane (HMDS), ammonium sulfate, 2) trimethylsilyl triflate (TMSOTf) / 1) reflux, 1 h, 2) 1,2-dichloroethane, a) -22 deg C, 15 min, b) room temperature, 0.5 h<br />4: 85.5 percent / methanol; H₂O / 18 h / 85 &deg;C<br /> <br /> &nbsp;

&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1098229', constants.ctx, '0')">methanol</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '3587155', constants.ctx, '0')">water</a> <br />T=85&deg;C;&nbsp;18&nbsp;h;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 7 steps<br /> </b>1: 98 percent / imidazole / dimethylformamide / 1 h / Ambient temperature<br />2: 1) lithium hexamethyldisilazide / 1) THF, -78 deg C, 1h, 2) room temperature, 30 min<br />3: tetrahydrofuran / -78 &deg;C<br />4: DIBAL-H / toluene / 2 h / -78 &deg;C<br />5: 96 percent / pyridine, DMAP / CH₂Cl₂ / 2 h / 0 &deg;C<br />6: 1) hexamethyldisilazane (HMDS), ammonium sulfate, 2) trimethylsilyl triflate (TMSOTf) / 1) reflux, 1 h, 2) 1,2-dichloroethane, a) -22 deg C, 15 min, b) room temperature, 0.5 h<br />7: 85.5 percent / methanol; H₂O / 18 h / 85 &deg;C<br /> <br /> &nbsp;