Isobomeol Isobomyl acetate

Isoamyl salicylate Isobomeol Isobomyl acetate Isobomyl formate Jsobomyl propionate... 

Isobomyl acetate [125-12-2] is also usehil ia produciag isobomeol (42) by saponiftcatioa. Dehydrogeaatioa or oxidatioa of isobomeol... 

Most synthetic camphor (43) is produced from camphene (13) made from a-piuene. The conversion to isobomyl acetate followed by saponification produces isobomeol (42) ia good yield. Although chemical oxidations of isobomeol with sulfuric/nitric acid mixtures, chromic acid, and others have been developed, catalytic dehydrogenation methods are more suitable on an iadustrial scale. A copper chromite catalyst is usually used to dehydrogenate isobomeol to camphor (171). Dehydrogenation has also been performed over catalysts such as ziac, iadium, gallium, and thallium (172). 

Isobomeol to Camphor. Nitric add has been widely used in the production of synthetic camphor from turpentine. The commonly accepted general practice for this manufacture (the one adapted by Gubehnann fw use in this country) involves the following steps (1) distillation of turpentine to obtain pinene, (2) saturation with HCl gas to obtain bomyl chloride, (3) hydrolyzing this to obtain camphene, (4) esterifying camphene to isobomyl acetate, (5) saponification to isobomeol, and (6) oxidation to camphor. 

Saponification of isobomyl acetate produces isobomeol exo -1,7,7-trimethylbicyclo [2.2.1]heptan-2-ol [124-76-5]) (119), which can be oxidized or dehydrogenated to give camphor (120). 

Most synthetic camphor is produced from a-pinene (20) via camphene (27), as shown in Fig. 8.24. Addition of acetic acid to camphene gives isobomyl acetate (117), which is saponified to produce isobomeol (119) in good yield. Catalytic dehydrogenation of iso-borneol then gives camphor. Catalysts include copper chromite (319) or metals, such as zinc, indium, gallium, and thallium (320). 

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