Cinnamaldehyde Hydroxyl

Pyrolytic Decomposition. The pyrolytic decomposition at 350—460°C of castor oil or the methyl ester of ricinoleic acid spHts the ricinoleate molecule at the hydroxyl group forming heptaldehyde and undecylenic acids. Heptaldehyde, used in the manufacture of synthetic flavors and fragrances (see Elavors and spices Perfumes) may also be converted to heptanoic acid by various oxidation techniques and to heptyl alcohol by catalytic hydrogenation. When heptaldehyde reacts with benzaldehyde, amyl cinnamic aldehyde is produced (see Cinnamic acid, cinnamaldehyde, and cinnamyl... 

The (S,S)-enantiomer of 62, but not 62 itself, is available from cinnamaldehyde via an asymmetric hydroxylation reaction involving fermenting Baker s yeast Fronza, G. Fuganti, C. Grasselli, P. J. Chem. Soc., Chem. Commun. 1980, 442. 

UV spectra of neutral solutions of ALCELL lignins exhibited maximum at 205-210 nm and at 275-281 nm which are characteristic of other lignin preparations. Alkali-neutral difference spectra exhibited three maxima at about 252-254 nm, 296-300 and 363-366 nm which indicate the presence of aromatic hydroxyl, a-conjugated hydroxyls, and conjugated carbonyl groups. The latter includes carbonyl groups in the a-position as well as those in cinnamaldehyde units mentioned above. The alkali-neutral difference spectrum of ALCELL lignins reduced with sodium borohydride shows an almost complete elimination of the peak at 360-366 nm and an increase... 

Chalcone, chromone, flavone, /rans-cinnamaldehyde, cyclopentenone, etc. gave the corresponding products in satisfactory yields [28], The oxidation of some disub-stituted a,j8-unsaturated cyclic ketones, however, gave predominantly hydroxylated products [29], An interesting variation was the synthesis of ds-hydroxyflavanones from 2-hydroxychalcones, e.g. [30] ... 

Reactions with unsaturated compounds. /-Butyl hydroperoxide decomposes smoothly at 95-105° and hydroxylates double bonds, and even a,)3-unsaturated ketones the reactions are catalyzed by small amounts of osmium tetroxide and afford cir-glycols. In benzene solution in the presence of Triton B as catalyst it converts a ,/3-unsaturated ketones into the corresponding epoxides in yields of 50-90%. The steric requirement of the base-catalyzed reaction are indicated by the failure to react with isophorone or A -3-ketosteroids. Payne effected smooth preparation of /3-phenylglycidaldehyde by allowing cinnamaldehyde and /-butyl... 

Dakin and Dakin-like Reactions Cinnamaldehydes or aromatic structures containing carbonyl substituents para to a free phenolic hydroxyl group (e.g., p-hydroxy-acetophenones) react with stabilized alkaline peroxide to form benzaldehydes and hydroquinones, respectively [37,38], Structures containing aryl-a-carbonyl substituents para to an etherilied phenolic group are degraded more slowly [39]. 

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