Presentation Title

The Challenges of Hydrophophinylation During Surfactant Synthesis

Faculty Mentor

Sylvine Deprele

Start Date

18-11-2017 12:30 PM

End Date

18-11-2017 1:30 PM

Location

BSC-Ursa Minor 73

Session

Poster 2

Type of Presentation

Poster

Subject Area

biological_agricultural_sciences

Abstract

In our quest of synthesizing an environmental friendly, phosphorus-based surfactant we have developed a precise synthetic route. Our work currently involves two synthetic methods in order to achieve the three-step synthesis leading to our surfactant “Silicon method” (SM) and the “Dean Stark method” (DSM). The SM consists of the transesterification of ethylphosphonate, generated by the reaction between hypophosphorous acid and TEOS (tetraethyl orthosilicate). In our hands, the SM has achieved high product yields; results have shown that with nonanol and 2-pentanol yielded up to 93% product and 61% product respectively, thus encouraging us to move onto the second step of our synthesis. This step involves elongating the nonpolar chain with a bromoalkene and a palladium catalyst to produce alkyl (5-bromo-pentyl) phosphinates. However, since moving onto Step 2, the SM has yet to consistently produce high yields due to, we believe the relative competition between the side products in the reaction. Consequently, we have been contemplating the use of the DSM, which is a method that removes water during the direct esterification of the hypophosphorous acid. The DSM holds advantage that limits the formation of side products that could interfere with the hydrophosphinylation, but, in our hands, it also has been observed to having the capacity to form pyrophoric P(III) species. Considering the current challenges, we have been able to determine that through the DSM, low but consistent yields were obtained in Step 2. Results show that nonanol at 1.5 equivalence and 2 equivalence as well as 2-pentanol at 1 equivalences respectively yield 56%, 54%, 44% and 44%. Currently, both methods present considerable challenges, thus we are continuing our study in both methods, side by side, using a scope of different solvents and alcohols to see if consistent yields can be obtained and to further our knowledge of Step 2.

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Nov 18th, 12:30 PM Nov 18th, 1:30 PM

The Challenges of Hydrophophinylation During Surfactant Synthesis

BSC-Ursa Minor 73

In our quest of synthesizing an environmental friendly, phosphorus-based surfactant we have developed a precise synthetic route. Our work currently involves two synthetic methods in order to achieve the three-step synthesis leading to our surfactant “Silicon method” (SM) and the “Dean Stark method” (DSM). The SM consists of the transesterification of ethylphosphonate, generated by the reaction between hypophosphorous acid and TEOS (tetraethyl orthosilicate). In our hands, the SM has achieved high product yields; results have shown that with nonanol and 2-pentanol yielded up to 93% product and 61% product respectively, thus encouraging us to move onto the second step of our synthesis. This step involves elongating the nonpolar chain with a bromoalkene and a palladium catalyst to produce alkyl (5-bromo-pentyl) phosphinates. However, since moving onto Step 2, the SM has yet to consistently produce high yields due to, we believe the relative competition between the side products in the reaction. Consequently, we have been contemplating the use of the DSM, which is a method that removes water during the direct esterification of the hypophosphorous acid. The DSM holds advantage that limits the formation of side products that could interfere with the hydrophosphinylation, but, in our hands, it also has been observed to having the capacity to form pyrophoric P(III) species. Considering the current challenges, we have been able to determine that through the DSM, low but consistent yields were obtained in Step 2. Results show that nonanol at 1.5 equivalence and 2 equivalence as well as 2-pentanol at 1 equivalences respectively yield 56%, 54%, 44% and 44%. Currently, both methods present considerable challenges, thus we are continuing our study in both methods, side by side, using a scope of different solvents and alcohols to see if consistent yields can be obtained and to further our knowledge of Step 2.