Three-component coupling of acylphosphonates and two carbonyl compounds promoted by low-valent samariums: One-pot synthesis of beta-hydroxyphosphonates

Three-component coupling of acylphosphonates and two carbonyl compounds lea ding to beta-hydroxyphosphonates has been achieved with low-valent samarium s. Thus, acylphosphonates reacted with aldehydes in the presence of semicat alytic amounts of samarium metal or SmI2 to give acyloxy-phosphonates in go od yields. The second coupling reaction of the acyloxyphosphonates with ald ehydes or ketones promoted by SmI2 afforded beta-hydroxyphosphonates instea d of olefins. Moreover, these two reactions could be carried out in one pot .