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Iron-catalyzed aminohydroxylation of olefins.

ABSTRACT: We have discovered that N-sulfonyl oxaziridines react with a broad range of olefins in the presence of iron salts to afford 1,3-oxazolidines. This process provides access to 1,2-aminoalcohols with the opposite sense of regioselectivity produced from the copper-catalyzed oxyamination previously reported by our laboratories. Thus, either regioisomeric form of 1,2-aminoalcohols can easily be obtained from the reaction of oxaziridines with olefins, and the sense of regioselectivity can be controlled by the appropriate choice of inexpensive, nontoxic, first-row transition-metal catalyst.

SUBMITTER: Williamson KS

PROVIDER: S-EPMC2857537 | BioStudies | 2010-01-01

REPOSITORIES: biostudies

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Iron catalyzed asymmetric oxyamination of olefins.

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Anionic halocuprate(II) complexes as catalysts for the oxaziridine-mediated aminohydroxylation of olefins.

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Copper-catalyzed [1,2]-rearrangements of allylic iodides and aryl ?-diazoacetates.

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Silicon-oriented regio- and enantioselective rhodium-catalyzed hydroformylation.

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1000-01-01 | S-EPMC5966446 | BioStudies

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Project description:The hydroxyamination reagent Br-N-(CO2Me)2 underwent Markovnikov addition to various olefins in the presence of catalytic BF3·OEt2 and provides efficient access to aminoalcohols. The reaction provided the trans-1-bromo, 2-N-bis-carbamate adduct stereoisomer in all cases. The resulting adduct underwent cyclization to give an oxazolidinone, which could be readily hydrolyzed to an oxazolidin-2-one or an amino alcohol.

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Highly regio- and enantioselective multiple oxy- and amino-functionalizations of alkenes by modular cascade biocatalysis.

Project description:New types of asymmetric functionalizations of alkenes are highly desirable for chemical synthesis. Here, we develop three novel types of regio- and enantioselective multiple oxy- and amino-functionalizations of terminal alkenes via cascade biocatalysis to produce chiral ?-hydroxy acids, 1,2-amino alcohols and ?-amino acids, respectively. Basic enzyme modules 1-4 are developed to convert alkenes to (S)-1,2-diols, (S)-1,2-diols to (S)-?-hydroxyacids, (S)-1,2-diols to (S)-aminoalcohols and (S)-?-hydroxyacids to (S)-?-aminoacids, respectively. Engineering of enzyme modules 1 &2, 1 &3 and 1, 2 &4 in Escherichia coli affords three biocatalysts over-expressing 4-8 enzymes for one-pot conversion of styrenes to the corresponding (S)-?-hydroxyacids, (S)-aminoalcohols and (S)-?-aminoacids in high e.e. and high yields, respectively. The new types of asymmetric alkene functionalizations provide green, safe and useful alternatives to the chemical syntheses of these compounds. The modular approach for engineering multi-step cascade biocatalysis is useful for developing other new types of one-pot biotransformations for chemical synthesis.

2016-01-01 | S-EPMC4911676 | BioStudies

A study of the scope and regioselectivity of the ruthenium-catalyzed [3 + 2]-cycloaddition of azides with internal alkynes.

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