Photoinduced intramolecular cyclopentanation vs photoprotolytic oxametathesis in polycyclic alkenes outfitted with conformationally constrained aroylmethyl chromophores.
نویسندگان
چکیده
Intramolecular photoinduced cyclizations are investigated in photoprecursors assembled in a modular fashion via a Diels-Alder reaction of acetylenic dienophiles with subsequent Michael additions of aromatic ketones to install a chromophore capable of initiating Paternò-Büchi cycloadditions or radical cyclization cascades. The protolytic oxametathesis in these systems allows for rapid access to novel polycyclic scaffolds decorated by formyl groups and carboxylates suitable for subsequent modifications. In conformationally constrained photoprecursors, a radical rearrangement takes place resulting in intramolecular 1,3-diradical cyclopentanation of the double bond.
منابع مشابه
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ورودعنوان ژورنال:
- The Journal of organic chemistry
دوره 78 5 شماره
صفحات -
تاریخ انتشار 2013