Bomylene

Camphene is the only well-recognised terpene which occurs in nature in the solid condition. It occurs, like pinene, in both optically active forms. The constitution of this terpene has been a matter of considerable difference of opinion, and the constitution assigned to it by Semmler based on its similarity to bomylene was thought by many to be finally accepted. Recent researches, however, have clearly established that the formula assigned to it by Wagner is the correct one. 

The procedure described above is essentially that of Thomas.2 Nor-bomylene has also been prepared by the additon of ethylene to monomeric cyclopentadiene 3 [Org. Syntheses, 32, 41 (1952)], by dehydration of j3-norbomeol with phosphorus pentoxide,4 and by dehydrohalogena-tion of norbornyl chloride or bromide using quinoline.4-6... 

The name campbene, from a nomenclature point of view, immediately suggests a bi-cyclic hydrocarbon similar to camphane but containing one double bond in the ring. That particular formula, however, has been called exclusively bomylene (Formula 89, Chart 13) in the terpene literature. The well-known campbene (Formula 84,... 

Camphane Bornylane Dihydrobomylene i Boroane. (l,7tt7 TriC metBylO oorboraane) 89. Bomylene J S 2-Bomene (1,7,7-trimethyl 2-norboraene )... 

Rule 4 Form the names of bivalent radicals derived from the four fundamental types of saturated bicyclic terpene hydrocarbons and having the two points of attachment on the same carbon by adding "idene to the names of the saturated univalent radicals. The resulting names are thujylidene, carylidene, pinanyl-idene, bornylidene. If the bivalent radicals derived from the saturated structures have the two points of attachment on different carbon atoms, add "ene to the names of the saturated univalent radical names. The resulting names are thujylene, carylene, pinanylene, bomylene. 

From bomylene they obtained isobomeol (V) and epibomeol (VI) nitrates ... 

The seobutyllithium was purchased from Alfa Products, Ventron Corp., and standardized by double titration or diphenylacetic acid titration. Other alkyllithium bases such as butyllithium and methyllithium cannot be substituted for the stronger sec-butyllithium since larger amounts of bomylene are formed because of incomplete dianion formation. Careful attention must be paid to stoichiometry in this reaction failure to do so also results in increasing the amount of bomylene formed. 

Even under ideal conditions the NMR of crude product shows 20-30% bomylene, which, however, is easily separated from the desired product during distillation as a forerun which sublimes into the vacuum pump trap. 

The most important of all of the oxygen derivatives of the terpene hydrocarbons are those of the di-cyclic group. Of these the most common is the well-known substance camphor, also termed Japan camphor. It is a ketone derivative of a di-cyclic terpene of the cam-phane type known as Bomylene. The corresponding alcohol derivative is known as Bomeol, or Borneo camphor. 

These azides undergo Curtius rearrangement to vinyl isocyanates, which are prone to polymerization. Where polymerization does not interfere, hydrolysis of the vinyl isocyanate provides aldehydes or ketones via the enamine. Bomylene carbonyl azide (47) yielded epicamphor (48) via the Curtius rearrangement-hydrolysis sequence. ... 

Bomylen.oarbons ure-(3)-e8ter des 2-Idethyl.butanolt.(2) 9 II60. 

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