- Synthesis of Long-Chain n-Alkylphosphonic Acids by Phosphonylation of Alkyl Bromides with Red Phosphorus and Superbase under Micellar/Phase Transfer Catalysis
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Long-chain n-Alkylphosphonic acids, AlkP(O)(OH)2, are synthesized in up to 91 % yield (mostly 40–60 %) by straightforward phosphonylation of alkyl bromides (AlkBr, Alk=C4–C18) with red phosphorus (Pn) in the multiphase KOH/H2O/toluene system in the presence of 2–10 mol % of cetyltrimethylammonium bromide (CTAB), acting as a micellar/phase transfer catalyst and as a generator/transporter of superbasic hydroxide anions, the intermediate potassium phosphinates being in situ oxidized/neutralized by nitric acid. The key steps of the phosphonylation mechanism are the P?P bond cleavage of Pn polymeric molecules by superbasic ?OH anions, dissolved in the CTAB micelles, and phase transfer of polyphosphide anions to the organic phase and their alkylation with AlkBr.
- Kuimov, Vladimir A.,Malysheva, Svetlana F.,Belogorlova, Natalia A.,Albanov, Alexander I.,Gusarova, Nina K.,Trofimov, Boris A.
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supporting information
p. 1596 - 1602
(2021/03/03)
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- Novel n-hexylphosphonic acid preparation method
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The invention belongs to the technical field of organic chemical preparation, and especially relates to a preparation method of electron grade novel n-hexylphosphonic acid. The preparation method comprises following steps: 1-bromohexane, and triethyl phosphite are mixed, an obtained mixture is heated to 130 to 150 DEG C, is reacted for 5 to 10h, is cooled, and is subjected to underpressure distillation to remove excess raw materials so as to obtain a N-hexyl phosphate; an appropriate amount of hydrochloric acid is added, heating backflow is carried out for 24 to 48h, and cooling and toluene extraction are carried out; an obtained toluene layer is subjected to active carbon decolouring, and is washed with deionized water and hydrochloric acid, and condensation is carried out so as to obtaincrude product; the crude product is subjected to crystallization purification using an organic solvent so as to obtain electron grade novel n-hexylphosphonic acid with a metal ion content lower than1ppm. The raw materials are easily available; the cost is low; operation is safe and convenient; the preparation method is suitable for industrialized production; and production efficiency is increased.
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Paragraph 0031-0036
(2018/10/11)
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- Synthesis and polymerization kinetics of acrylamide phosphonic acids and esters as new dentine adhesives
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In restorative dentistry, acrylamide monomers bearing phosphonic acid moieties have proved to be useful species for the formulation of dental self-etch adhesives since they provide enhanced adhesion to hydroxyapatite and are not subject to hydrolysis, thus potentially improving their adhesive durability. Previous studies have demonstrated that phosphonic acid acrylamides increase the rate of photopolymerization of diacrylamide monomers. To understand whether this rate acceleration is specific to the acrylamide function of the monomer, or due to the phosphonic acid group per se, or is applicable only with a crosslinking reaction, we have synthesized several acrylamide and methacrylate monomers bearing phosphonic acid or phosphonate moieties and studied their photopolymerization kinetics. The acrylamide phosphonic acid was found to accelerate the polymerization rate but similar monomers bearing a phosphonate ester group had a much smaller effect. A similar accelerating effect was observed when the phosphonic acid-based monomers were copolymerized with a monofunctional acrylamide monomer, excluding the possibility that the rate acceleration might be related to the crosslinking process. This rate effect is also observed when a nonpolymerizable organic phosphonic acid is present in the polymerizing medium. We suggest that the increase of the medium polarity is responsible for this rate enhancement effect.
- Besse,Le Pluart,Cook,Pham,Madec
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p. 149 - 157
(2013/01/16)
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