- Umpolung Strategy for Arene C?H Etherification Leading to Functionalized Chromanes Enabled by I(III) N-Ligated Hypervalent Iodine Reagents
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The direct formation of aryl C?O bonds via the intramolecular dehydrogenative coupling of a C?H bond and a pendant alcohol represents a powerful synthetic transformation. Herein, we report a method for intramolecular arene C?H etherification via an umpoled alcohol cyclization mediated by an I(III) N-HVI reagent. This approach provides access to functionalized chromane scaffolds from primary, secondary and tertiary alcohols via a cascade cyclization-iodonium salt formation, the latter providing a versatile functional handle for downstream derivatization. Computational studies support initial formation of an umpoled O-intermediate via I(III) ligand exchange, followed by competitive direct and spirocyclization/1,2-shift pathways. (Figure presented.).
- Mikhael, Myriam,Guo, Wentao,Tantillo, Dean J.,Wengryniuk, Sarah E.
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- Cannabidiol derivative as well as preparation method and medical application thereof
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The invention relates to a cannabidiol derivative and application thereof in medicine, in particular to a pyrimidine derivative as shown in a general formula (I), or a stereoisomer, a solvate, a metabolite, a pharmaceutically acceptable salt or a co-crystal thereof, with definition of each substituent in the general formula (I) being the same as that in the specification.
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Paragraph 0215-0224
(2021/07/10)
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- Cannabidiol derivative as well as preparation method and medical application thereof
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The invention relates to a cannabidiol derivative and application thereof in medicine, in particular to a pyrimidine derivative as shown in a general formula (I), or a stereoisomer, a solvate, a metabolite, a prodrug, a pharmaceutically acceptable salt or a co-crystal thereof, and definition of each substituent in the general formula (I) is the same as that in the specification.
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Paragraph 0092; 0096-0102
(2021/07/10)
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- Synthesis of tetrahydrocannabinols based on an indirect 1,4-addition strategy
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The synthetic procedure presented for the preparation of the title compounds requires 1,4-addition of bulky cuprates to cyclohexenones and subsequent reaction with electrophiles. However, the enolates generated by BF3·OEt2-assistance suffer from lack of nucleophilicity. To circumvent this problem, we developed an indirect method consisting of the following three steps: (1) iodination of the cyclohexenones at the α position; (2) BF3·OEt2-assisted 1,4-addition of cuprates (Ar2Cu(CN)-Li2, Ar = aryl) followed by quenching the enolates with water; (3) reaction of the α-iodo-β-arylcylohexanones thus formed with EtMgBr to generate magnesium enolates. The enolates thus generated in this way showed a high reactivity toward ClP(O)(OEt)2 to furnish enol phosphates. The aforementioned procedure was also applied to a synthesis of optically active Δ9-tetrahydrocannabinol. In addition, a naphthalene analogue of the latter compound was also synthesized in a similar way.
- William, Anthony D.,Kobayashi, Yuichi
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p. 8771 - 8782
(2007/10/03)
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