Synthesize camphene

How does one easily synthesize camphene in the modern day? The old 1902 patent says to combine ammonia and pinene hydrochloride in an autoclave at 210-220C for 20 hours. Would alpha-pinene work with that process?




1. alpha-pinene can be isomerized using acid treated clay as the catalyst to produce camphene. (see references in the comments below)
2. Isolated Camphene can be naturally sourced from valerian (Valeriana officinalis) extracted via steam, expression, or cryogenic methods, and fractionally distilled for purity <http://www.tandfonline.com/doi/abs/10.1080/10412905.2008.9700079>


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