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Selective C-7 Functionalization of Phenanthridines by Microwave-Assisted Claisen Rearrangements of 8-Allyloxyphenanthridines.

ABSTRACT: Carbon-carbon bond formation in the phenanthridine 7-position was achieved by microwave-assisted Claisen rearrangement of 8-allyloxyphenanthridines. The reactions took place with excellent regioselectivity and high chemical yields. If the 7-position was substituted, rearrangement to C-9 took place, but the reaction occurred less readily. Rearrangements of 8-allyloxy-5,6-dihydrophenanthridines (phenanthridines with a saturated B-ring) gave a mixture of 7- and 9-substituted products. The experimental results were supported by DFT (density functional theory) calculations.

SUBMITTER: Lepsoe MR

PROVIDER: S-EPMC10362114 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Selective C-7 Functionalization of Phenanthridines by Microwave-Assisted Claisen Rearrangements of 8-Allyloxyphenanthridines.

Lepsøe Mathias Ryslett MR Dalevold Aleksander Granum AG Gundersen Lise-Lotte LL

ChemistryOpen 20230701 7

Carbon-carbon bond formation in the phenanthridine 7-position was achieved by microwave-assisted Claisen rearrangement of 8-allyloxyphenanthridines. The reactions took place with excellent regioselectivity and high chemical yields. If the 7-position was substituted, rearrangement to C-9 took place, but the reaction occurred less readily. Rearrangements of 8-allyloxy-5,6-dihydrophenanthridines (phenanthridines with a saturated B-ring) gave a mixture of 7- and 9-substituted products. The experimen ...[more]

PMID: 37480187

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