The acid-catalyzed rearrangement of epoxides 3a, 4a, 6a, and 7a derived from β-himachalene, the major constituent of Cedrus atlantica essential oil, has been studied using various Lewis and Bronsted acids. Several new enantiomerically pure ketones were obtained in good yields and high selectivities. All products obtained were fully characterized by 1H and 13C NMR, and the mechanistic explanations for their formation were proposed.

中文翻译：

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使用路易斯酸和布朗斯台德酸催化由β-喜马查烯半合成的环氧化物衍生物的重排

已经使用各种路易斯酸和布朗斯台德酸研究了酸催化重排环氧化物 3a、4a、6a 和 7a 的重排，这些环氧化物源自大西洋雪松精油的主要成分 β-喜马查烯。以良好的产率和高选择性获得了几种新的对映体纯酮。获得的所有产物均通过 1H 和 13C NMR 进行了充分表征，并提出了对其形成的机理解释。