1: NaI / acetone / 17 h / Heating 2: 12 percent / Bu3SnH, AIBN / benzene / 18 h / Heating; other time; other cyclic keto-compounds; three-carbon ring expansion to large rings View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '3587158', constants.ctx, '0')">hydrogen bromide</a> <br />&nbsp;Irradiation;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: 85 percent / NaH / benzene; paraffin / 1 h / Heating<br />2: 1) NaH, HMPA / 1) THF, mineral oil, r.t., 1 h, 2) reflux, 12 h<br />3: HBr(g) / pentane / 0.25 h / 0 &deg;C / Irradiation<br /> <br /> &nbsp;