A New Atom-Economical and Selective Synthesis of Secondary and Tertiary Alkylamines by Means of Cp*Iridium Complex Catalyzed Multiple N-Alkylation of Ammonium Salts with Alcohols without Solvent
synthesis of secondary and tertiaryamines has been achieved by means of Cp*Ir-catalyzed multialkylation of ammonium salts with alcohols without solvent: the reactions of ammonium acetate with alcohols gave tertiaryamines exclusively, while those of ammonium tetrafluoroborate afforded secondary amines selectively. Using this method, secondary 5- and 6-membered cyclic amines were synthesized from ammonium
A New Atom-Economical and Selective Synthesis of Secondary and Tertiary Alkylamines by Means of Cp*Iridium Complex Catalyzed Multiple N-Alkylation of Ammonium Salts with Alcohols without Solvent
A new atom-economical and selective synthetic method for secondary and tertiary alkylamines has been achieved by means of (pentamethylcyclopentadienyl)iridium (Cp*Ir) complex catalyzed multiple N-alkylations of ammonium salts with primary and secondary alcohols without solvent.
Unusual Orthogonality in the Cleavage Process of Closely Related Chelating Protecting Groups for Carboxylic Acids by Using Different Metal Ions
作者:Stephan Mundinger、Uwe Jakob、Willi Bannwarth
DOI:10.1002/chem.201302708
日期:2014.1.27
conditions, these protectinggroups are also stable under acidic and basic conditions, allowing them to be used in combination with the ester protection of carboxylic acids. The cleavage of these protectinggroups is activated by the chelation of metal ions, involving an unusual coordination of the amide nitrogen. Despite their similarity, cleavage of these protectinggroups is possible in both a stepwise
Novel water-soluble Cp*Ir-ammine complexes have been synthesized, and a new and highly atom-economical system for the synthesis of organic amines using aqueous ammonia as a nitrogen source has been developed. With a water-soluble and air-stable Cp*Ir-ammine catalyst, [Cp*Ir(NH3)(3)][1](2), a variety of tertiary and secondary amines were synthesized by the multialkylation of aqueous ammonia with theoretical equivalents of primary and secondary alcohols. The catalyst could be recycled by a facile procedure maintaining high activity. A one-flask synthesis of quinolizidine starting with 1,5,9-nonanetriol was also demonstrated. This new catalytic system would provide a practical and environmentally benign methodology for the synthesis of various organic amines.