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C-H bond functionalization via hydride transfer: synthesis of dihydrobenzopyrans from ortho-vinylaryl akyl ethers.

ABSTRACT: The hydride transfer initiated cyclization ("HT-cyclization") of aryl alkyl ethers, which leads to direct coupling of sp(3) C-H bonds and activated alkenes, is reported. Readily available salicylaldehyde derived ethers are converted in one step to dihydrobenzopyrans, an important class of heteroarenes frequently found in biologically active compounds. This process has not been previously reported, in contrast to known HT-cyclizations of the corresponding tert-amines ("tert-amino effect" reactions).

SUBMITTER: McQuaid KM

PROVIDER: S-EPMC2954889 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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C-H bond functionalization via hydride transfer: synthesis of dihydrobenzopyrans from ortho-vinylaryl akyl ethers.

McQuaid Kevin M KM Long Jonathan Z JZ Sames Dalibor D

Organic letters 20090701 14

The hydride transfer initiated cyclization ("HT-cyclization") of aryl alkyl ethers, which leads to direct coupling of sp(3) C-H bonds and activated alkenes, is reported. Readily available salicylaldehyde derived ethers are converted in one step to dihydrobenzopyrans, an important class of heteroarenes frequently found in biologically active compounds. This process has not been previously reported, in contrast to known HT-cyclizations of the corresponding tert-amines ("tert-amino effect" reaction ...[more]

PMID: 19548698

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