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