Multicomponent Mannich Reactions with Boron Enolates Derived from Diazo Esters and 9-BBN.
Summary of "Multicomponent Mannich Reactions with Boron Enolates Derived from Diazo Esters and 9-BBN."
Diazo esters, arylboranes, and carbamoyl imines undergo a 3-component Mannich condensation reaction. Catalyzed by Cu(II) salts, the reaction affords the corresponding isocyanate Mannich product: one that can be easily trapped in situ by other nucleophiles. The Mannich condensation corresponds to an α,α-disubstituted enolate addition to imines. The reaction was rendered asymmetric by using the (-)-phenylmenthol ester in good yield and selectivities.
Affiliation
Department of Chemistry, Center for Chemical Methodology and Library Development (CMLD-BU), Boston University , Boston, Massachusetts 02215, United States.
Journal Details
This article was published in the following journal.
Name: Organic letters
ISSN: 1523-7052
Pages: 2510-3
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21473584
- DOI: http://dx.doi.org/10.1021/ol200766t
Medical and Biotech [MESH] Definitions
Boron
A trace element with the atomic symbol B, atomic number 5, and atomic weight 10.81. Boron-10, an isotope of boron, is used as a neutron absorber in BORON NEUTRON CAPTURE THERAPY.
Mannich Bases
Ketonic amines prepared from the condensation of a ketone with formaldehyde and ammonia or a primary or secondary amine. A Mannich base can act as the equivalent of an alpha,beta unsaturated ketone in synthesis or can be reduced to form physiologically active amino alcohols.
Boron Compounds
Inorganic or organic compounds that contain boron as an integral part of the molecule.
Boron Neutron Capture Therapy
A technique for the treatment of neoplasms, especially gliomas and melanomas in which boron-10, an isotope, is introduced into the target cells followed by irradiation with thermal neutrons.
Microscopy, Electron
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
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