Nucleophilic transformations of cyclic phosphate triesters

作者：Ashkenazi N^*; Karton Y; Segall Y

来源：Tetrahedron Letters, 2004, 45(43): 8003-8006.

DOI：10.1016/j.tetlet.2004.09.011

• nucleophilic attacks
• Grignard reagents
• cyclic phosphate triesters
• phosphonates
• phosphites

Reactions of cyclic phosphate triesters, such as 2-ethoxy-1,3,2-dioxapliospholane 2-oxide, with Grignard reagents such as phenyl-, alkyl-, ethynyl-, and allyl-magnesium halides result in ring opening leading to the corresponding phosphonates, via nucleophilic attack of carbon on the phosphorus atom. Treatment of 2-ethoxy-1,3,2-dioxaphospholane 2-oxide with sodium borohydride yields ethyl 2-hydroxyethyl phosphite. This reaction is exclusive for the five-membered cyclic system: under these conditions acyclic phosphate triesters, such as triethyl phosphate, are unreactive and the analogous six-membered ring system, 2-ethoxy-1,3,2-dioxaphosphormane 2-oxide reacts only partially to give unidentified phosphate esters and traces of phosphonate products. Both compounds were inert to NaBH(4).

• 出版日期2004-10-18