2000 cycloaddition reactions

cycloaddition reactionsO 0070

38 - 038Synthesis of Bi- and Tricyclic Spiro Compounds on the Basis ofAlloocimene and Cyclopentadiene. — Diels–Alder reaction of α,β-unsaturated ketones, obtained in situ from cycloalkanones (II) under Mannichconditions, to alloocimene (I) or cyclopentadiene (XI) provides access to thecorresponding bi- or tricyclic spiro compounds (IV)/(V) and (XII), resp.,which are smoothly converted to the fragrant esters (IX)/(X) and (XV). —(SKUMOV, M. YA.; BALBOLOV, E. KH.; Russ. J. Org. Chem. 35 (1999) 9,1301-1307; Arsen Zlatarov Univ., BG-8010 Bourgas, Bulg.; EN)

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