Thorsten Rische

Supercritical carbon dioxide as solvent and temporary protecting group for rhodium-catalyzed hydroaminomethylation.

Supercritical carbon dioxide (scCO2) acts simultaneously as solvent and temporary protecting group during homogeneously rhodium-catalyzed hydroaminomethylation of ethyl methallylic amine. Cyclic amines are formed as the major products in scCO,, whereas the cyclic amide is formed preferentially in conventional solvents. Multinuclear high-pressure NMR spectroscopy revealed that this selectivity switch is mainly due to reversible formation of the carbamic acid in the solvent CO2, which reduces the tendency for intramolecular ring closure at the Rh-acyl intermediate. These results substantiate the general concept of using scCO2 as a protective medium for amines in homogeneous catalysis and demonstrate for the first time its application for selectivity control.

One-pot synthesis of pharmacologically active secondary and tertiary 1-(3,3-diarylpropyl)amines via rhodium-catalysed hydroaminomethylation of 1,1-diarylethenes

Abstract Pharmacologically active secondary and tertiary 1-(3,3-diarylpropyl)amines 1 are prepared in high yields and chemoselectivity by the reaction of 1,1-diarylethenes 4, primary or secondary amines 5, carbon monoxide and hydrogen in presence of [Rh(cod)Cl] 2 PBu 3 as catalyst via a one-pot hydroformylation - amine condensation - reduction sequence.

Selective one-pot synthesis of symmetrically and unsymmetrically substituted amines via rhodium catalysed multiple alkylations of ammonia or primary amines under hydroformylation conditions

Abstract Symmetrically and unsymmetrically substituted secondary and tertiary amines are selectively prepared in high yields by a one-pot multiple alkylation procedure from ammonia or primary amines with styrenes and/or cyclic olefins, carbon monoxide and hydrogen in the presence of [Rh(cod)Cl] 2 as catalyst. Similarly unsymmetrically substituted tertiary amines are obtained under hydroformylation conditions from primary amines by a one-pot reductive bisalkylation procedure using preformed aldehydes or ketones in one step and the hydroformylation products in the second step of a combined amine condensation - reduction - hydroaminomethylation reaction sequence.

One-pot synthesis of pharmacologically active diamines via rhodium-catalysed carbonylative hydroaminomethylation of heterocyclic allylic amines

Abstract Pharmacologically active derivatives of phenothiazine, iminodibenzyl, carbazole and pyrazole are prepared with high yields and chemoselectivity by the reaction of the correspondingN-allylic orN-methallylic compounds, primary or secondary amines, carbon monoxide and hydrogen in the presence of [Rh(cod)Cl]2 as catalyst via a one pot hydroformylation - amine condensation - reduction sequence. Download : Download full-size image

Synthesis of γ-Amino- and δ-Amino-Functionalised Ethers, Amines, or Silanes by Hydroaminomethylation of Heterofunctionalised Allylic Compounds

Heterofunctionalised allylic ethers 1, silanes 5, and amines 9 are hydroformylated in the presence of primary or secondary amines 2 to form the corresponding γ-amino- and δ-amino-functionalised compounds. The rhodium(I)-catalysed reaction sequence proceeds by aldehyde formation and subsequent reductive amination to generate the corresponding functionalised secondary or tertiary amines. This selective one-pot hydroaminomethylation procedure establishes access to γ-amino- and δ-amino-functionalised ethers, amines or silanes with potential biological activity.

One-pot synthesis of secondary and tertiary naphthylpropylamines by rhodium(I)-catalysed carbonylative hydroaminomethylation

Abstract Secondary and tertiary naphthylpropylamines are prepared in high yields by the reaction of 2-vinylnaphthalene, primary or secondary amines, carbon monoxide and hydrogen in presence of [Rh(cod)Cl] 2 as catalyst via a one-pot hydroformylation - amine condensation - reduction sequence.

One-pot synthesis of β- and γ-aminofunctionalised amines and silanes via hydroaminomethylation of enamines and vinylsilanes

Abstract Heterofunctionalised enamines and vinylsilanes under hydroformylation conditions in the presence of primary or secondary amines are converted to form diamines or aminosilanes in one step. This selective one-pot hydroaminomethylation procedure establishes an easy and convenient access to β- and γ-aminofunctionalised amines and silanes with potential biological activity.

Selective one-pot synthesis of secondary and tertiary amines via rhodium catalysed reduction and multiple alkylation of aromatic nitro compounds under hydroformylation conditions

Abstract Secondary and tertiary amines are selectively prepared in high yields by a one-pot reduction / multiple alkylation procedure from aromatic nitro compounds with styrenes, cyclic olefins or heterofunctionalised olefins, carbon monoxide and hydrogen in the presence of [Rh(cod)Cl] 2 as catalyst.

ONE-POT SYNTHESIS OF 1,4-DIAMINES FROM ALLYL HALIDES AND AMINES VIA A RHODIUM-CATALYSED MULTISTEP REACTION SEQUENCE UNDER HYDROFORMYLATION CONDITIONS

Abstract 1,4-Diamines 8 are prepared with good yields and selectivities by the reaction of methallyl chloride ( 6 ), secondary amines 7 , carbon monoxide and hydrogen in presence of [Rh(cod)Cl] 2 as catalyst via a one-pot nucleophilic substitution - hydroformylation - amine condensation - reduction sequence.