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Synthesis and Reactions of Benzannulated Spiroaminals: Tetrahydrospirobiquinolines.

ABSTRACT: An efficient two-step synthesis of symmetrical and unsymmetrical tetrahydrospirobiquinolines from o-azidobenzaldehydes is reported. A novel series of tetrahydrospirobiquinolines was prepared by sequential double-aldol condensation with acetone, cyclopentanone, and cyclohexanone to form the corresponding o,o'-diazido-dibenzylidene-acetone, -cyclopentanone, and -cyclohexanone derivatives, respectively, and hydrogenation-spirocyclization. The spirodiamines were further derivatized by electrophilic aromatic bromination, Suzuki coupling, and N-alkylation, all of which proceeded with preservation of the spirocyclic core.

SUBMITTER: Almond-Thynne J

PROVIDER: S-EPMC6044889 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Synthesis and Reactions of Benzannulated Spiroaminals: Tetrahydrospirobiquinolines.

Almond-Thynne Joshua J White Andrew J P AJP Polyzos Anastasios A Rzepa Henry S HS Parsons Philip J PJ Barrett Anthony G M AGM

ACS omega 20170707 7

An efficient two-step synthesis of symmetrical and unsymmetrical tetrahydrospirobiquinolines from o-azidobenzaldehydes is reported. A novel series of tetrahydrospirobiquinolines was prepared by sequential double-aldol condensation with acetone, cyclopentanone, and cyclohexanone to form the corresponding o,o'-diazido-dibenzylidene-acetone, -cyclopentanone, and -cyclohexanone derivatives, respectively, and hydrogenation-spirocyclization. The spirodiamines were further derivati ...[more]

PMID: 30023690

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