The Structure of Umbellulone Dibromide¹

Vibronic Interaction in Potassium o-Xylenide

“…In summary, the above and previous data5 suggest the following with respect to the rearrange- (7) The labeled perchlorate was prepared from the corresponding amine which in turn was prepared by reduction of propionitrile-2,2-¿2 with lithium aluminum deuteride. The propionitrile-2,2-¿2 was prepared according to L. C. Leitch, Can.…”

Terpenes. V. Preferred conformation and spectral properties of some optically active 2-cyclopenten-1-ones

“…boxylic acid (3).5 These three compounds were obtained through the bromination of ( -)-umbeliulone (4)4-6 and subsequent transformations of 1, one of the products of this bromination reaction (see Scheme I).4-6 The configuration of each of these ketones had been deduced by the oxidation of 3 to (iS)-a-methyl-aisopropylsuccinic acid (5),5,6 a compound of known absolute configuration.7-9…”

The Relative Stability of Bridged Hydrocarbons. Norbornene and Nortricyclene1

“…Norbornene (I) and Nortricyclene (II).-Pure norbornene was prepared by the Diels-Alder reaction of ethylene with cyclopentadiene.19 The homogeneity of this material was shown by the following observations: (1) Oxidation with sodium permanganate gave cis-1,3-cyclopentanedicarboxylic acid in 95% yield20 (nortricyclene was reported to be unaffected by potassium permanganate).11 (2) Quantitative microhydrogenation under mild conditions resulted in the uptake of 97.3 and 98.8% of the theoretical quantity of hydrogen.21 (3) Fractional distillation through ail efficient column gave substance of constant boiling point (96.0°a t 760 mm.) and of constant melting point (46.0-46.5°), which represented over 80% of the material collected.…”