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Towards a Catalytic Atroposelective Synthesis of Diaryl Ethers via C(sp 2)-H Alkylation Using Nitroalkanes.

ABSTRACT: Herein we report studies towards a small molecule catalytic approach to access atropisomeric diaryl ethers that proceeds via a C(sp 2)-H alkylation using nitroalkanes as the alkyl source. A quaternary ammonium salt derived from quinine containing a sterically hindered urea at the C-9 position was found to effect atroposelective C(sp 2)-H alkylation with moderate to good enantioselectivities across several naphthoquinone-containing diaryl ethers. Products can then be isolated in greater than 95:5 er after one round of trituration. For several substrates that were evaluated we observed a 'nitroethylated' product in similar yields and selectivities.

SUBMITTER: Dinh AN

PROVIDER: S-EPMC6550490 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Towards a Catalytic Atroposelective Synthesis of Diaryl Ethers via C(sp 2)-H Alkylation Using Nitroalkanes.

Dinh Andrew N AN Noorbehesht Ryan R RR Toenjes Sean T ST Jackson Amy C AC Saputra Mirza A MA Maddox Sean M SM Gustafson Jeffrey L JL

Synlett : accounts and rapid communications in synthetic organic chemistry 20180731 16

Herein we report studies towards a small molecule catalytic approach to access atropisomeric diaryl ethers that proceeds via a C(sp 2)-H alkylation using nitroalkanes as the alkyl source. A quaternary ammonium salt derived from quinine containing a sterically hindered urea at the C-9 position was found to effect atroposelective C(sp 2)-H alkylation with moderate to good enantioselectivities across several naphthoquinone-containing diaryl ethers. Products can t ...[more]

PMID: 31178629

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