Experimental evidence of a cyclopropylcarbinyl conjugative electronic effect.
نویسندگان
چکیده
Bicyclo[3.2.0]hept-2-enes undergo thermal rearrangement to norbornenes via diradical transition structures. The synthesis of exo-7-cyclopropylbicyclo[3.2.0]hept-2-ene has been achieved by cycloaddition of cyclopentadiene and cyclopropylketene, generated by treatment of cyclopropylacetyl chloride with triethylamine. A comparison of the cyclopropyl substituent effect with that of other C7 substituents provides experimental evidence of an electron-donating conjugative effect on the transient diradical transition structure in the thermal reaction of exo-7-cyclopropylbicyclo[3.2.0]hept-2-ene.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 36 شماره
صفحات -
تاریخ انتشار 2013