72448-73-8

Upstream product

• 100-44-7 benzyl chloride 
• 1205-62-5 4-nitrobenzylphosphonic acid 
• 78-39-7 Triethyl orthoacetate 
• 1080-32-6 O,O-diethyl benzylphosphonate 
• 18933-98-7 benzylphosphonic acid monoethyl ester 

Downstream Products

• 185457-34-5 ethyl (4-nitrobenzyl)phosphonochloridate 

Relevant academic research and scientific papers

Selective esterification of phosphonic acids

Here, we report straightforward and selective synthetic procedures for mono-and diesteri-fication of phosphonic acids. A series of alkoxy group donors were studied and triethyl orthoacetate was found to be the best reagent as well as a solvent for the performed transformations. An important temperature effect on the reaction course was discovered. Depending on the reaction temperature, mono-or diethyl esters of phosphonic acid were obtained exclusively with decent yields. The sub-strate scope of the proposed methodology was verified on aromatic as well as aliphatic phosphonic acids. The designed method can be successfully applied for small-and large-scale experiments without significant loss of selectivity or reaction yield. Several devoted experiments were performed to give insight into the reaction mechanism. At 30?C, monoesters are formed via an intermediate (1,1-diethoxyethyl ester of phosphonic acid). At higher temperatures, similar intermediate forms give diesters or stable and detectable pyrophosphonates which were also consumed to give diesters.31P NMR spectroscopy was used to assign the structure of pyrophosphonate as well as to monitor the reaction course. No need for additional reagents and good accessibility and straightforward purification are the important aspects of the developed protocols.

Synthetic Strategy and Performances of a UV-Curable Poly Acryloyl Phosphinate Flame Retardant by Carbene Polymerization

A route to synthesize poly ethyl (4-acrylamidebenzyl) phosphinate (PPAC) was discussed and the optimal route was determined. Diethyl benzylphosphonate was synthesized by Arbuzov reaction, then, a nitryl was introduced onto the aromatic ring by the nitration reaction of ethyl benzylphosphonate. Subsequently the carbene polymerization of the product was carried out. Finally, the nitryls were reduced and amidated to introduce the acryloyl group into the prepolymer to obtain the target product (PPAC). PPAC can rapidly photopolymerize under UV light irradiation. The addition of PPAC decreased the smoke production rate (SPR), CO2 production (CO2P), and CO production (COP) of the UV-cured resin.

Photochemical C-P Bond Cleavage of Nitrobenzylphosphonate Ions

Upon UV-irradiation, the C-P bond of p-nitrobenzylphosphonate ions cleaved with a quantum yield of about 0.7 in an aqueous alcohol solution to give 1,2-bis(4-nitrophenyl)ethane, p-nitrotoluene, orthophosphate, and alkyl dihydrogenphosphate.Whereas in an aqueous solution 1,2-bis(4-nitrophenyl)ethane was produced as a main product, in an alcohol solution only p-nitrotoluene was produced.This photolysis may proceed via intramolecular electron tranfer from PO32- group to nitro aromatic moiety to form an excited state, which undergoes C-P bond cleavage to give p-nitrobenzyl anion and monomeric metaphosphate anion as intermediates.The C-P bond cleavage of p-nitrobenzylphosphonate ion occurred more readily than those of o- and m-nitrobenzylphosphonate ions.

Photochemical Carbon-Phosphorus Bond Cleavage of Nitro-substituted Benzylphosphonic Acids

Upon u.v.-irradiation, the C-P bond of p-nitrobenzylphosphonate is more readily cleaved to give a monomeric metaphosphate anion as intermediate than those of o- and m-derivatives.