Syntheses, spectral property, and antimicrobial activities of 6‐α‐amino dibenzo [d,f][1,3,2]dioxaphosphepin 6‐oxides

Diethyl α-aminophosphonates (4) were prepared in excellent yield from three-component reaction of aldehydes (1), amines (2), and triethylphosphite (3) under solvent-free conditions in the presence of ceric ammonium nitrate (CAN) and were reacted with 2,2′-dihydroxybiphenyl (5) using p-toluene sulfonic acid monohydrate (PTSA) as a catalyst to obtain 6-α-aminodibenzo[d f][1,3,2]dioxaphosphepin 6-oxides (6) in good yield. It is a first report on the cyclizations of 4 with 5. An antimicrobial activity of numbers of 6 is evaluated. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:2–8, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20244