- Microwave-assisted esterification of P-acids
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The possibilities for the preparation of dialky phenylphosphonates were evaluated. On the one hand, the oxidation of phenyl-H-phosphinates gave the corresponding phenylphosphonic acid monoesters. On the other hand, phenylphosphonates may be prepared by MW-assisted direct esterification of phenylphosphonic acid. The reaction with alcohols was performed under MW irradiation in the presence of an ionic liquid as the catalyst. The second ester function was established by alkylating esterification carried out with alkyl halides in the presence of triethylamine under MW conditions.
- ábrányi-Balogh, Péter,Harsági, Nikoletta,Keglevich, Gy?rgy,Kiss, Nóra Zsuzsa
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- Synthesis of phosphonates from phenylphosphonic acid and its monoesters
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Possibilities for the mono- and diesterification of phenylphosphonic acid were evaluated considering the microwave(MW)-assisted direct esterification, and the alkylating esterification. It was found that regarding the monoesterification, the reaction with 15-fold alcohol excess in the presence of [bmim][BF4] additive utilizing MWs is superior than the approach by alkylation. At the same time, for the conversion of the monoester intermediate to the diester, the reaction with alkyl halides in the presence of triethylamine as the base, again under MW irradiation, was found to be the method of choice. Phosphonates with both identical and different alkoxy groups were made available.
- Henyecz, Réka,Kiss, Adrienn,Mórocz, Virág,Kiss, Nóra Zsuzsa,Keglevich, Gy?rgy
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supporting information
p. 2642 - 2650
(2019/08/08)
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- Selective Substitution of POCl 3 with Organometallic Reagents: Synthesis of Phosphinates and Phosphonates
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The selectivity of the substitution reaction of phosphoryl chloride with organometallic reagents was investigated using NMR spectroscopy. This led to the discovery that the selectivity of the substitution reaction can be tuned by choosing a proper organometallic reagent. A phosphinate could be obtained by using a Grignard reagent whereas an organozinc reagent provided a phosphonate. Based on these results, one-pot synthetic methods for the preparation of phosphinates and phosphonates using commercially available starting materials were developed. Both methods allow the synthesis of a broad range of either phosphinate or phosphonate derivatives in a straightforward and general procedure. Moreover, using these one-pot procedures, mixed systems substituted with different alkyl/aryl groups can be prepared.
- Verbelen, Bram,Dehaen, Wim,Binnemans, Koen
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p. 2019 - 2026
(2018/04/14)
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