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Ruthenium catalyzed C-C bond formation via transfer hydrogenation: branch-selective reductive coupling of allenes to paraformaldehyde and higher aldehydes.

ABSTRACT: Under the conditions of ruthenium-catalyzed transfer hydrogenation employing 2-propanol as the terminal reductant, 1,1-disubstituted allenes 1a- h engage in reductive coupling to paraformaldehyde to furnish homoallylic alcohols 2a- h. Under identical transfer hydrogenation conditions, 1,1-disubstituted allenes engage in reductive coupling to aldehydes 3a- f to furnish homoallylic alcohols 4a- n. In all cases, reductive coupling occurs with branched regioselectivity to deliver homoallylic alcohols bearing all-carbon quaternary centers.

SUBMITTER: Ngai MY

PROVIDER: S-EPMC2845390 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Ruthenium catalyzed C-C bond formation via transfer hydrogenation: branch-selective reductive coupling of allenes to paraformaldehyde and higher aldehydes.

Ngai Ming-Yu MY Skucas Eduardas E Krische Michael J MJ

Organic letters 20080606 13

Under the conditions of ruthenium-catalyzed transfer hydrogenation employing 2-propanol as the terminal reductant, 1,1-disubstituted allenes 1a- h engage in reductive coupling to paraformaldehyde to furnish homoallylic alcohols 2a- h. Under identical transfer hydrogenation conditions, 1,1-disubstituted allenes engage in reductive coupling to aldehydes 3a- f to furnish homoallylic alcohols 4a- n. In all cases, reductive coupling occurs with branched regioselectivity to deliver homoallylic alcohol ...[more]

PMID: 18533665

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