Molecular geometry of .beta.-pinene as deduced from the crystal and molecular structure of cis-pinocarvyl-p-nitrobenzoate

Abstract

in press. (7) Methyl 2-hydroxyphenylacetate (12) cycllzed to 2-coumaranone (15) to varying extents during glc analysis. The yield reported for 12 has been corrected for this conversion.15 (8) In the Vycor-filtered reactions even at low conversions color developed in the reaction mixtures and a significant amount of the incident radiation was not being absorbed by the starting material. This situation prevented reliable quantum yield determinations. (9) A somewhat similar observation has been made by E. A. Caress and I. E.

Rotational strength sign and normal modes description: A theoretical and experimental comparative study in bicyclic terpenes

“…For comparison, in Table 1, it is shown the molecular parameters of b-pinene obtained from an X-ray study of the cis-pinocarvyl p-nitrobenzoate at 21938C. 32 As a For a-pinene and verbenone bond lengths of the common CÀ ÀC double bond and CÀ ÀC(methyl) are also shown. b Bond lengths in Å , angles in degrees.…”

Free-radical addition of tetrahalomethanes to β[beta]-pinene. Experiments in organic chemistry

“…Prior to the experiment the mechanism of addition of bromotrichloromethane to 1-octene, which illustrates the manner in which these reactions occur, is discussed (1, 22) and applied to the reaction with /?-pinene. The skeletal rearrangement accompanying the addition is interpreted as a means of relieving the angular strain of the four-membered ring system (16,23). At this point the possibility is considered that the addition step and the rearrangement may, or may not, be concerted.…”

Strain-Promoted Oxidation of Methylenecyclopropane Derivatives using N-Hydroxyphthalimide and Molecular Oxygen in the Dark

“…75 Reaction of trans-dioxasilacyclooctene 12 with NHPI proceeded selectively to yield 13, with the phthalimido-N-oxyl group in the pseudoequatorial orientation and oxygen introduced to form the preferred out,out-bicyclo[5.3.1]undecane ring system. 74,76 β-Pinene ( 14), which undergoes other strain-promoted reactions, 77,78 is not sufficiently strained to react under the present conditions, even upon irradiation. The β-hydroperoxy-N-alkoxyamine products formed in these reactions can be easily functionalized.…”

“…While NHPI appeared to add selectively to the less hindered exo face of the bicyclic system, molecular oxygen added to both the exo and endo faces due to its high rate of reaction with alkyl radicals . Reaction of trans -dioxasilacyclooctene 12 with NHPI proceeded selectively to yield 13 , with the phthalimido- N -oxyl group in the pseudoequatorial orientation and oxygen introduced to form the preferred out,out-bicyclo[5.3.1]­undecane ring system. , β-Pinene ( 14 ), which undergoes other strain-promoted reactions, , is not sufficiently strained to react under the present conditions, even upon irradiation.…”