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Generation and tandem reactions of 1-alkenyl-1,1-heterobimetallics: practical and versatile reagents for organic synthesis.
J Am Chem Soc. 2008 Mar 19; 130(11):3521-31.JA

Abstract

A practical and straightforward method for generation of versatile 1-alkenyl-1,1-heterobimetallic intermediates and their application to construction of functionalized building blocks are disclosed. Beginning with readily available air-stable 1-alkynyl-1-boronate esters, hydroboration with dicyclohexylborane generates 1-alkenyl-1,1-diboro species. In situ transmetallation with dialkylzinc reagents furnishes 1-alkenyl-1,1-heterobimetallic intermediates. Direct treatment with aldehydes followed by workup allows isolation of B(pin)-substituted allylic alcohols in 70-95% yield. The B(pin)-substituted allylic alcohols react with NBS to afford (E)-alpha,beta-unsaturated aldehydes in 51-77% yield via a semipinacol-type rearrangement. In situ treatment of 1-alkenyl-1,1-heterobimetallic intermediates with aldehydes followed by TBHP oxidation enables the preparation of alpha-hydroxy ketones. Under optimized conditions, addition of 1-alkenyl-1,1-heterobimetallic intermediates to a variety of protected alpha- and beta-hydroxy aldehydes proceeds with good to excellent control over diastereoselectivity to furnish differentially protected dihydroxy ketones. The 1-alkenyl-1,1-heterobimetallic intermediates have also been employed in tandem aldehyde addition/Suzuki cross-coupling reactions to provide densely functionalized allylic alcohols in good to excellent yields.

Authors+Show Affiliations

P. Roy and Diana T. Vagelos Laboratories, University of Pennsylvania, Department of Chemistry, 231 South 34th Street, Philadelphia, Pennsylvania, 19104-6323, USA.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

18302376

Citation

Li, Hongmei, et al. "Generation and Tandem Reactions of 1-alkenyl-1,1-heterobimetallics: Practical and Versatile Reagents for Organic Synthesis." Journal of the American Chemical Society, vol. 130, no. 11, 2008, pp. 3521-31.
Li H, Carroll PJ, Walsh PJ. Generation and tandem reactions of 1-alkenyl-1,1-heterobimetallics: practical and versatile reagents for organic synthesis. J Am Chem Soc. 2008;130(11):3521-31.
Li, H., Carroll, P. J., & Walsh, P. J. (2008). Generation and tandem reactions of 1-alkenyl-1,1-heterobimetallics: practical and versatile reagents for organic synthesis. Journal of the American Chemical Society, 130(11), 3521-31. https://doi.org/10.1021/ja077664u
Li H, Carroll PJ, Walsh PJ. Generation and Tandem Reactions of 1-alkenyl-1,1-heterobimetallics: Practical and Versatile Reagents for Organic Synthesis. J Am Chem Soc. 2008 Mar 19;130(11):3521-31. PubMed PMID: 18302376.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Generation and tandem reactions of 1-alkenyl-1,1-heterobimetallics: practical and versatile reagents for organic synthesis. AU - Li,Hongmei, AU - Carroll,Patrick J, AU - Walsh,Patrick J, Y1 - 2008/02/27/ PY - 2008/2/28/pubmed PY - 2008/4/30/medline PY - 2008/2/28/entrez SP - 3521 EP - 31 JF - Journal of the American Chemical Society JO - J Am Chem Soc VL - 130 IS - 11 N2 - A practical and straightforward method for generation of versatile 1-alkenyl-1,1-heterobimetallic intermediates and their application to construction of functionalized building blocks are disclosed. Beginning with readily available air-stable 1-alkynyl-1-boronate esters, hydroboration with dicyclohexylborane generates 1-alkenyl-1,1-diboro species. In situ transmetallation with dialkylzinc reagents furnishes 1-alkenyl-1,1-heterobimetallic intermediates. Direct treatment with aldehydes followed by workup allows isolation of B(pin)-substituted allylic alcohols in 70-95% yield. The B(pin)-substituted allylic alcohols react with NBS to afford (E)-alpha,beta-unsaturated aldehydes in 51-77% yield via a semipinacol-type rearrangement. In situ treatment of 1-alkenyl-1,1-heterobimetallic intermediates with aldehydes followed by TBHP oxidation enables the preparation of alpha-hydroxy ketones. Under optimized conditions, addition of 1-alkenyl-1,1-heterobimetallic intermediates to a variety of protected alpha- and beta-hydroxy aldehydes proceeds with good to excellent control over diastereoselectivity to furnish differentially protected dihydroxy ketones. The 1-alkenyl-1,1-heterobimetallic intermediates have also been employed in tandem aldehyde addition/Suzuki cross-coupling reactions to provide densely functionalized allylic alcohols in good to excellent yields. SN - 1520-5126 UR - https://www.unboundmedicine.com/medline/citation/18302376/Generation_and_tandem_reactions_of_1_alkenyl_11_heterobimetallics:_practical_and_versatile_reagents_for_organic_synthesis_ DB - PRIME DP - Unbound Medicine ER -