pyridinium chlorochromate in dichloromethane T=20°C; Molecular sieve;

triethylsilane; trifluoroacetic acid

1.1: pyridinium chlorochromate / dichloromethane / 20 °C / Molecular sieve 2.1: BBr3*DMSO / dichloromethane / 3 h / 0 °C 2.2: 0.17 h / cooling with ice View Scheme

Stage #1: <a href="#" onclick="return RXDsubstances(event, this, '506892', constants.ctx, '0')">methoxybenzene</a> <b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '103296', constants.ctx, '0')">2,2,6,6-tetramethyl-piperidine</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '1209227', constants.ctx, '0')">n-butyllithium</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '8127938', constants.ctx, '0')">cobalt(II) dibromide</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '1730733', constants.ctx, '0')">hexane</a> <br />T=0 - 20&deg;C;&nbsp;2&nbsp;h;&nbsp;<br />Stage #2: <a href="#" onclick="return RXDsubstances(event, this, '471382', constants.ctx, '0')">4-methoxy-benzaldehyde</a> &nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '1730733', constants.ctx, '0')">hexane</a> <br />T=-50 - 20&deg;C;&nbsp;&nbsp;Reagent/catalyst;&nbsp;<br /> <br /> &nbsp;

Stage #1: &nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a> <br />T=0 - 20&deg;C;&nbsp;<br />Stage #2: <b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '3587155', constants.ctx, '0')">water</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '4371014', constants.ctx, '0')">ammonium chloride</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a> <br /> <br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '18267074', constants.ctx, '0')">chloro(η⁴-1,5 -cyclooctadiene)-bis(pyrrolidinecarbene)rhodium(I)</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '3556712', constants.ctx, '0')">potassium <i>tert</i>-butylate</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1209237', constants.ctx, '0')">ethylene glycol dimethyl ether</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '3587155', constants.ctx, '0')">water</a> <br />T=80&deg;C;&nbsp;1&nbsp;h;&nbsp;&nbsp;Inert atmosphere;&nbsp;<br /> &nbsp;

Stage #1: <a href="#" onclick="return RXDsubstances(event, this, '1237590', constants.ctx, '0')">1-bromo-4-methoxy-benzene</a> <b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1209227', constants.ctx, '0')">n-butyllithium</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a> <br />T=-78&deg;C;&nbsp;&nbsp;Inert atmosphere;&nbsp;<br />Stage #2: <a href="#" onclick="return RXDsubstances(event, this, '606301', constants.ctx, '0')">ortho-anisaldehyde</a> T=20&deg;C;&nbsp;5&nbsp;h;&nbsp;<br /> &nbsp;

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