The chemical reactivity of cannabidiol is based on its ability to undergo intramolecular cyclization driven by the addition of a phenolic group to one of its two double bonds. The main products of this cyclization are Δ⁹-THC (trans-Δ-9-tetrahydrocannabinol) and Δ⁸-THC (trans-Δ-8-tetrahydrocannabinol). These two cannabinoids are isomers, and the first one is a frequently investigated psychoactive compound and pharmaceutical agent. The isomers Δ⁸-iso-THC (trans-Δ-8-iso-tetrahydrocannabinol) and Δ⁴⁽⁸⁾-iso-THC (trans-Δ-4,8-iso-tetrahydrocannabinol) have been identified as additional products of intramolecular cyclization. The use of Lewis and protic acids in different solvents has been studied to investigate the possible modulation of the reactivity of CBD (cannabidiol). The complete NMR spectroscopic characterizations of the four isomers are reported. High-performance liquid chromatography analysis and ¹H NMR spectra of the reaction mixture were used to assess the percentage ratio of the compounds formed.

中文翻译：

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大麻二酚作为酸催化分子内环化的底物

大麻二酚的化学反应性基于其通过向其两个双键之一添加酚基而进行分子内环化的能力。该环化的主要产物是Δ ⁹ -THC（反式-Δ-9-四氢大麻酚）和Δ ⁸ -THC（反式-Δ-8-四氢大麻酚）。这两种大麻素是异构体，第一种是经常研究的精神活性化合物和药剂。异构体 Δ ⁸ - iso -THC ( trans -Δ-8- iso -tetrahydrocannabinol) 和 Δ ⁴⁽⁸⁾ - iso -THC ( trans -Δ- ^4,8 - iso-四氢大麻酚）已被确定为分子内环化的附加产物。已经研究了路易斯酸和质子酸在不同溶剂中的使用，以研究 CBD（大麻二酚）反应性的可能调节。报告了四种异构体的完整 NMR 光谱表征。反应混合物的高效液相色谱分析和¹ H NMR光谱用于评估形成的化合物的百分比。