2026-04-17T04:16:08Zhttps://recercat.cat/oai/request
oai:recercat.cat:2445/1645782025-12-05T14:22:03Zcom_2072_1057col_2072_478816col_2072_478917col_2072_478923col_2072_478924
RECERCAT author Camps García, Pelayo author Gómez Nadal, Tània author Otermin Esteras, Ane author Font Bardia, Ma. Mercedes author Estarellas, Carolina author Luque Garriga, F. Xavier 2020-06-06T08:18:06Z2020-06-06T08:18:06Z2015-08-202020-06-06T08:18:06Z Two domino Diels-Alder adducts were obtained from 3,7-bis(cyclopenta-2,4-dien-1-ylidene)-cis-bicyclo[3.3.0]octane and dimethyl acetylenedicarboxylate or N-methylmaleimide under microwave irradiation. From the first adduct, a C20H24 diene with C2v symmetry was obtained by Zn/AcOH reduction, hydrolysis, oxidative decarboxylation and selective hydrogenation. Photochemical [2+2] cycloaddition of this diene gave a thermally unstable cyclobutane derivative, which reverts to the diene. However, both diene and cyclobutane derivatives could be identified by X-ray diffraction analysis upon irradiation of the diene crystal. New six-membered rings are formed upon transannular addition of bromine or iodine to the diene. The N-type selectivity of the addition was examined by theoretical calculations which revealed the distinct susceptibility of the doubly bonded carbon atoms to the bromine attack. (c) Wiley-VCH, 2015 info:eu-repo/semantics/openAccess Reaccions químiques Fotoquímica Difusió de raigs X Chemical reactions Photochemistry X-ray scattering Short access to belt compounds with spatially close C=C bonds and their transannular reactions info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion