Russian Journal of General Chemistry, Vol. 74, No. 10, 2004, pp. 1627!1628. Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1750 !1751. Original Russian Text Copyright + 2004 by Shekhade, Didkovskii, Dogadina, Ionin.
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Reaction of Acetylenediphosphonates with Methyl or Ethyl Malonates A. Shekhade, N. G. Didkovskii, A. V. Dogadina, and B. I. Ionin St. Petersburg State Institute of Technology, St. Petersburg, Russia Received June 30, 2004
Acetylenedicarboxylic esters are known to condense with methyl and ethyl malonates to form complex cyclic compounds [1]. We found that the reaction of phosphorus analogs of acetylenedicarboxylic esters, viz. acetylenediphosphonates, with methyl or ethyl malonates under basic catalysis conditions follows a usual nucleophilic addition scheme to form (E)-alkenediphosphonates I!IV. The reaction was performed in acetonitrile in the presence of anhydrous K2CO3. It was complete in 2 h. The reaction progress was monitored by means of 1H, 31 P NMR and 1H3{31P} NMDR spectroscopy. During the reaction, in the NMDR spectra the 31P resonance signal of the starting acetylenediphosphonate at dP ~11 ppm decreased and then disappeared completely,
while that of final (E)-alkenediphosphonate I!IV increased. After completion of the reaction, the protondecoupled 31P NMR spectra showed 31P signals as an AB system (dA ~12 and dB ~16 ppm, 3JPP 107 Hz). The value of the coupling constant indicates trans arrangement of the phosphorus-containing groups. The value of the vicinal coupling constant of the vinyl proton with phosphorus, 3JHP 25 Hz, provides evidence for this configuration assessment. In all experiments, the 1H NMR spectra of the reaction mixtures lacked signal of the malonate proton of final compounds I!IV. The 13C NMR spectra of the reaction mixtures displayed a triplet signal in the region of dC 71 ppm. The proton-coupled spectra revealed no proton on the corresponding carbon atom. These data point to formation of potassium derivatives of phosphorylated CH acids I!IV.
E A A E *E
ÄÄÄÄÄÄÄÄÄÄÄÄ K2CO3
(RO)2P(O)C=CP(O)(OR)2 + CH2(COOR`)2 776
H
P(O)(OR)2
!KHCO3 (RO)2(O)P
C(COOR`)2
76
P(O)(OR)2
(RO)2(O)P
C(COOR`)2 H I!IV
K
R = Me, R` = Me (I), Et (II); R = Et, R` = Me (III), Et (IV).
After removal of K2CO3/KHCO3, the reaction mixtures were treated with an equivalent trifluoroacetic acid to isolate quantitatively phosphorylated vinylmalonates I!IV with preserved E configuration. The 1H NMR spectra, along with a doubled doublet signal of the vinyl proton in the region of 6 ppm (JHP ~25, JHP ~15 Hz), contain a doubled doublet signal of the malonate methine proton at d ~5.3 ppm. In the proton-decoupled 13C NMR spectra, the carbon signal of the malonate group is shifted upfield relative to that of the potassium derivative and appears as a triplet near dC 51 ppm with approximately equal coupling
E A A E *E
H
ÄÄÄÄÄÄÄÄÄÄÄÄ
constants with two phosphorus nuclei, 2,3JCP 9 Hz. In P NMR spectra, CH diphosphonates I!IV give an AB system, dP ~10312 and ~13315 ppm, 3JPP 883 89 Hz.
31
The intermediate potassium derivatives turned to be fairly stable compounds. Under the action of alcohol, the hydrogen exchange for potassium is complete after 3 days only, and the reaction products undergo isomerization. Under the action of deuteromethanol, potassium and then hydrogen atoms are gradually substituted by deuterium.
1070-3632/04/7410-1627 C2004 MAIK
[Nauka/Interperiodica]
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SHEKHADE et al.
As known, potassium carbonate is a weak catalyst in such nucleophilic addition and substitution reactions, and its activity is commonly enhanced by using crown ethers [2]. Probably, in the reaction with acetylenediphosphonate, the substrate phosphoryl groups behave like crown ethers, and this provides successful reaction and stabilization of the potassium derivatives formed. Dimethyl 2,3-bis(dimethoxyphosphinoyl)vinylmalonate (I). 1H NMR spectrum (CDCl3), d, ppm: 3.45 s (6H, OCH3), 3.45 d (6H, CH3OP, 3JHP 11.2 Hz), 3.55 d (6H, CH3OP, 3JHP 11.2, 3JHP 11.2 Hz), 5.29 d.d (1H, CH, 3JHP 22.2 Hz, 4JHP 3.8 Hz), 6.38 d.d (1H, PCH, 2JHP 15.1, 3JHP 25.3 Hz). 13C NMR spectrum (CDCl3), dC, ppm: 51.29 t (CH, 2JPC 8.6, 3JPC 8.6 Hz), 52.14 d (CH3OP, 2JPC 6.2 Hz), 52.70 d (CH3OOC, 4JPC 6.2 Hz), 133.53 d.d (CHP, 1 JPC 163.0, 2JPC 17.1 Hz), 143.79 d.d (CP, 1 JPC 161.7, 2JPC 13.4 Hz), 166.03 s (CO). 31P NMR spectrum (CDCl3), dP, ppm: 12.91, 15.25 d (3JPP 88.0 Hz). Diethyl 2,3-bis(dimethoxyphosphinoyl)vinylmalonate (II). 1H NMR spectrum (CDCl3), d, ppm: 1.12, 1.15 t (6H, CH3, 3JHH 7.9 Hz), 3.42 d (6H, CH3OP, 2JHP 10.9 Hz), 3.45 d (6H, CH3OP, 2JHP 10.9 Hz), 5.20 d (1H, CH, 3JHP 22.8, 4JHP 3.9 Hz), 6.30 d.d (1H, PCH, 2JHP 14.6, 3JHP 25.2 Hz). 13C NMR spectrum (CDCl3), dC, ppm: 13.42 s (CH3), 51.25 t (CH, 2JPC 9.0, 3JPC 9.0 Hz), 51.90 d (CH3OP, 2 JPC 6.3 Hz), 52.39 d (CH3OP, 2JPC 6.3 Hz), 61.02 s (CH2), 133.17 d.d (PCH, 1JPC 163.7, 2JPC 18.3 Hz), 143.78 d.d (CP, 1JPC 161.9, 2JPC 13.8 Hz), 165.36 s (CO). 31P NMR spectrum (CDCl3), dP, ppm: 14.02, 16.43 d (3JPP 89.8 Hz). Dimethyl 2,3-bis(diethoxyphosphinoyl)vinylmalonate (III). 1H NMR spectrum (CDCl3), d, ppm: 1.15, 1.17 t (12H, CH3, 3JHH 7.0 Hz), 3.58 s (6H, CH3O), 3.90, 3.92 d.q (8H, CH2OP, 3JHH 7.0, 3JHP
10.0 Hz), 5.46 d.d (1H, CH, 3JHP 22.6, 4JHP 3.6 Hz), 6.59 d.d (1H, PCH, 2JHP 14.6, 3JHP 25.6 Hz). 13C NMR spectrum (CDCl3), dC, ppm: 15.74 s (CH3), 51.33 t (CH, 2JPC 9.0, 3JPC 9.0 Hz), 52.35 s (CH3O), 61.83 d (CH2OP, 2JPC 6.5 Hz), 62.53 d (CH2OP, 2JPC 6.5 Hz), 135.08 d.d (CHP, 1JPC 164.0, 2JPC 19.9 Hz), 143.88 d.d (CP, 1JPC 162.6, 2JPC 13.9 Hz), 166.33 s (CO). 31P NMR spectrum (CDCl3), dP, ppm: 10.64, 13.00 d (3JPP 89.0 Hz). Diethyl 2,3-bis(diethoxyphosphinoyl)vinylmalonate (IV). 1H NMR spectrum (CDCl3), d, ppm: 1.14, 1.12, 1.15 t (18H, CH3, 3JHH 8.2 Hz), 3.91, 4.05 d.q (8H, CH2OP, 3JHH 8.2, 3JHP 11.1, 4JHP 4.0 Hz), 4.12 q (4H, CH2OO), 5.35 d.d (1H, CH, 2JHP 22.4, 4JHP 4.0 Hz), 6.62 d.d (1H, CHP, 2JHP 14.6, 3JHP 25.8 Hz). 13C NMR spectrum (CDCl3), dC, ppm: 13.30 s (CH3), 15.68 s (CH3), 51.34 t (CH, 2JPC 9.5, 3 JPC 9.5 Hz), 61.23 s (OCH2), 61.26 d (CH2OP, 2JPC 5.7 Hz), 61.76 d (CH2OP, 2JPC 5.7 Hz), 134.29 d.d (CHP, 1JPC 163.1, 2JPC 18.6 Hz), 144.31 d.d (CP, 1JPC 162.7, 2JPC 13.1 Hz), 165.76 s (CO). 31P NMR spectrum (CDCl3), dP, ppm: 11.41, 13.77 d (3JPP 88.9 Hz). The 1H, 13C and 31P NMR spectra were registered on a Bruker C-200 spectrometer at 200.132 (1H), 50.328 (13C) and 81.014 (31P) MHz, solvents carbon tetrachloride and deuterochloroform, internal references TMS (1H) and CDCl3 (13C), external reference 85% phosphoric acid (31P). The 1H3{31P} NMDR spectra were registered on a Tesla BS-497 spectrometer (100 MHz).
REFERENCES 1. Acetylenes, Viehe, H.G., Ed., New York: Marcel Dekker, 1969. 2. http://courses.chem.psu.edu/chem36/Experiments/ Exp13.pdf; Thompson, D.L. and Reeves, P.C., J. Chem. Educ., 1985, vol. 62, no. 10, p. 907.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
Vol. 74
No. 10
2004