boron trifluoride diethyl etherate in dichloromethane 1.) -40 deg C, 1 h, 2.) warmed to R.T. over 12 h.;

1: 83 percent / p-toluenesulfonic acid / 3 h / 90 °C 2: 42 percent / benzene / Irradiation View Scheme

&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '103233', constants.ctx, '0')">pyridine</a> <br />0.5&nbsp;h;&nbsp;&nbsp;Heating;&nbsp;<br /> &nbsp;

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