The composition of Eucalyptus and some other leaf waxes

Abstract

Many Eucalyptus waxes contain as major components long-chain β-diketones, which may be readily separated from the rest of the wax as insoluble copper complexes. The most commonly occurring β-diketone is n-tritriacontan-16,18-dione, but in two species, Eucalyptus risdoni and E. coccifera, β-diketones of shorter chain length predominate. From the waxes of several Eucalyptus species a new flavone, 5-hydroxy- 4',7-dimethoxy-6,8-dimethylflavone, and a new triterpene, 11,l2-dehydroursolic lactone acetate, have been isolated. Gas chromatography has been used to determine the chain length distribution of β-diketones, hydrocarbons, and esters from several waxes. The esterified alcohols of Eucalyptus globulus and E. risdoni belong to two series-long-chain n-alkan-1-ols of predominantly even carbon number, and n-alkan-2-ols of medium chain length and predominantly uneven carbon number (n-C9, n-C11, n-C13, and n-C15).

Composition of the leaf wax of Little Club wheat

“…0-Diketones were removed from the wax (1965) as copper complexes (3,5) but part of the alcohols crystallized at the same time. The resulting mixture of P-diketones, alcohols, and hydroxy-P-diketones was separated chromatographically.…”

Rapid and efficient biphasic liquid extraction of metals with bio-derived lipophilic β-diketone

“…4 The lipophilic β-diketone, 1, was isolated using an adapted method described by Horn et al previously reporting the extraction from eucalyptus. 13 Through the chelation of 1 with copper acetate (Cu(OAc) 2 ) it was possible to recover a yield of 18 ±0.5wt% from wheat straw wax. The 1 H-NMR, 13 C-NMR, MS…”

“…13 Through the chelation of 1 with copper acetate (Cu(OAc) 2 ) it was possible to recover a yield of 18 ±0.5wt% from wheat straw wax. The 1 H-NMR, 13 C-NMR, MS…”

New Rare Earth Antiknock Additives that are Potential Substitutes for Tetraethyl Lead

“…Waxes from various grasses and Eucalyptus and Acacia species contain 50% or more a-diketones [34,35].…”