Synthesis of Compound 53 with G1 by ene-yne RCM

To a solution of Grubbs catalyst G1 (943 mg, 1.15 mmol, 0.4 equiv) in CH2C12 (900 mL) was added a solution of enyne 51 (2.00 g, 2.86 mmol, 1.0 equiv) in toluene (100mL). The reaction was purged with ethylene and stirred at 45 °C under an atmosphere of ethylene for 40 h. The crude mixture was treated with ethyl vinyl ether (1 mL) and concentrated to a black oil. Purification by silica gel chromatography (doped with triethylamine, 5-6% in CH2Cl2/hexane) afforded cyclophane 53 (624 mg, 31%). 

Financial support was provided by the CNRS and the Ecole Polytechnique. 

4CC-IMDA 4-component condensation/intramolecular Diels-Alder reaction sequence 

2645-2648. The metathesis reaction is performed on the enantiomer of 83 in this case. 

Dietrich-Buchecker, C., Rapenne, G. and Sauvage, J.-P. (1997) Chem. Commun., 2053-2054. 

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