Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

• Erika Bálint,
• Ádám Tajti,
• Anna Dzielak,
• Gerhard Hägele and
• György Keglevich

Beilstein J. Org. Chem. 2016, 12, 1493–1502, doi:10.3762/bjoc.12.146

• , triethyl orthoformate and two equivalents of diphenylphosphine oxide. The method is also suitable for the preparation of (aminomethylene)bisphosphonates using (MeO)2P(O)H/(MeO)3CH or (EtO)2P(O)H/(EtO)3CH reactant pairs and even secondary amines. Several intermediates referring to the reaction mechanism

• together with a few by-products could also be identified. Keywords: (aminomethylene)bisphosphine oxides; (aminomethylene)bisphosphonates; microwave; three-component condensation; Introduction Substituted (hydroxymethylene)bisphosphonic acid derivatives form an important group of drugs used in the

• antibacterial, antiparasitic, anticancer and herbicidal activities [5]. (Aminomethylene)bisphosphonates may be prepared in different ways [5]. One of the most convenient and widespread methods is the three-component condensation involving an amine, an orthoformate and a dialkyl phosphite. Usually, primary or