TY - JOUR

T1 - Features of the identification of trialkyl phosphites in reaction mixtures and their characterization by gas chromatography - mass spectrometry

AU - Zenkevich, I. G.

AU - Nosova, V. E.

N1 - Zenkevich, I.G. & Nosova, V.E. J Anal Chem (2019) 74: 1305. https://doi.org/10.1134/S1061934819130124

PY - 2019/12

Y1 - 2019/12

N2 - The interaction of aliphatic alcohols ROH with phosphorus trichloride in the absence of bases leads to the formation of exclusively dialkyl phosphonates (RO)2PHO. To obtain trialkyl phosphites (RO)3P, insufficiently described to date, the pH of the reaction mixtures was adjusted by adding N,N-dimethylaniline (pKa 5.1 ± 0.1). The identification of trialkyl phosphites directly in reaction mixtures without preparative isolation implies a joint consideration of their mass spectra and gas chromatographic retention indices, provided that all other components of such mixtures are identified. The need to comply with this condition has led to the identification of several homologues of a previously uncharacterized series of 2-alkoxy-1,3,2-dioxaphospholanes, formed from a random admixture of ethylene glycol. The use of such combined mass spectrometric parameters as homologous increments of retention indices helps to distinguish trialkyl phosphites from isobaric dialkyl phosphonates; the compounds of both series belong to the homologous group of y = 12, y ≡ M(mod14). Despite the absence of molecular ion signals in the electron ionization (EI) mass spectra, the molecular weights of trialkyl phosphites can be estimated. In addition, a comparison of the homologous increments of retention indices shows that, compared with dialkyl phosphonates, trialkyl phosphites are significantly less polar.

AB - The interaction of aliphatic alcohols ROH with phosphorus trichloride in the absence of bases leads to the formation of exclusively dialkyl phosphonates (RO)2PHO. To obtain trialkyl phosphites (RO)3P, insufficiently described to date, the pH of the reaction mixtures was adjusted by adding N,N-dimethylaniline (pKa 5.1 ± 0.1). The identification of trialkyl phosphites directly in reaction mixtures without preparative isolation implies a joint consideration of their mass spectra and gas chromatographic retention indices, provided that all other components of such mixtures are identified. The need to comply with this condition has led to the identification of several homologues of a previously uncharacterized series of 2-alkoxy-1,3,2-dioxaphospholanes, formed from a random admixture of ethylene glycol. The use of such combined mass spectrometric parameters as homologous increments of retention indices helps to distinguish trialkyl phosphites from isobaric dialkyl phosphonates; the compounds of both series belong to the homologous group of y = 12, y ≡ M(mod14). Despite the absence of molecular ion signals in the electron ionization (EI) mass spectra, the molecular weights of trialkyl phosphites can be estimated. In addition, a comparison of the homologous increments of retention indices shows that, compared with dialkyl phosphonates, trialkyl phosphites are significantly less polar.

KW - trialkyl phosphites

KW - 2-alkoxy-1,3,2-dioxaphospholanes

KW - gas chromatographic retention indices

KW - homologous increments of retention indices

KW - EI mass spectra

KW - detection in the composition of reaction mixtures

UR - https://link.springer.com/article/10.1134%2FS1061934819130124

M3 - Article

VL - 74

SP - 1305

EP - 1319

JO - Journal of Analytical Chemistry

JF - Journal of Analytical Chemistry

SN - 1061-9348

IS - 13

ER -