598-79-8Relevant articles and documents
A Straightforward Homologation of Carbon Dioxide with Magnesium Carbenoids en Route to α-Halocarboxylic Acids
Monticelli, Serena,Urban, Ernst,Langer, Thierry,Holzer, Wolfgang,Pace, Vittorio
supporting information, p. 1001 - 1006 (2019/01/30)
The homologation of carbon dioxide with stable, (enantiopure) magnesium carbenoids constitutes a valuable method for preparing α-halo acid derivatives. The tactic features a high level of chemocontrol, thus enabling the synthesis of variously functionalized analogues. The flexibility to generate magnesium carbenoids through sulfoxide-, halogen- or proton- Mg exchange accounts for the wide scope of the reaction. (Figure presented.).
Preparation of α-haloacrylate derivatives via dimethyl sulfoxide-mediated selective dehydrohalogenation
Li, Wei,Li, Jianchang,Wan, Zhao-Kui,Wu, Junjun,Massefski, Walter
, p. 4607 - 4610 (2008/03/13)
(Chemical Equation Presented) Dimethyl sulfoxide causes α/β-dihalopropanoate derivatives to undergo efficient, selective dehydrohalogenation to form α-haloacrylate analogues. A variety of α-halo Michael acceptors were prepared in dimethyl sulfoxide under mild, base-free conditions, including the preparation of α-bromoacrolein and α-chloro- and bromoacrylonitriles. Synthesis of these molecules has been reported in the literature to be difficult. Among all the existing dehydrohalogenation procedures, this protocol is the most facile, practical, and environmentally benign process.
Reaction of 2,3-dihalopropionic acids and their derivatives with P- and N-nucleophiles
Khachikyan,Tovmasyan,Indzhikyan
, p. 1889 - 1894 (2008/02/03)
3-(Triphenylphosphoniochlorido)acrylic and 2,3-dichloropropionic acids react with triphenylphosphine to form 1,2-bis(triphenylphosphoniochlorido) ethane. Under analogous conditions, 2,3-dibromopropionic acid undergoes debromination followed by triphenylphosphine addition to give, after water treatment, 3-(triphenylphosphoniobromido)propionic acid. 2,3- Dihalopropionitriles react similarly, providing 3-(triphenylphosphoniohalido) propionitriles. The reaction of 2,3-dibromopropionamide with triphenylphosphine was performed to show that E-(triphenylphosphoniobromido)acrylic acid is capable, by contrast to what was reported previously, of reacting with triphenylphosphine. Pyridine forms with 2,3-dihalopropionic acids vinylpyridinium halides, while the reactions with aliphatic amines gives rise to dehydrohalogenation products.
Conformational stability, barriers to internal rotation, vibrational assignment, and ab initio calculations of 2-chloropropenoyl fluoride
Durig, J. R.,Wang, A. Y.,Little, T. S.,Brletic, P. A.
, p. 905 - 917 (2007/10/02)
The far-infrared spectrum of gaseous 2-chloropropenoyl fluoride, CH2CClCFO, has been recorded at a resolution of 0.10 cm-1 in the region of 350-35 cm-1.The fundamental asymmetric torsional frequencies of the more stable s-trans (two double bonds oriented trans to one another) and the high energy s-cis conformations have been observed at 67.80 and 49.96 cm-1, respectively, each with several excited states falling to lower frequencies.From these data the asymmetric torsional potential function governing the internal rotation about the C-C bond has been determined.The potential coefficients are V1 = - 125 +/- 1, V2 = 1586 +/- 6, V3 = 375 +/- 2, V4 = - 36 +/- 2, and V5 = 65 +/- 1 cm-1.The s-trans to s-cis and s-cis to s-trans barriers have been determined to be 1755 and 1570 cm-1, respectively, with an energy difference between the conformations of 185 +/- 9 cm-1 (529 +/- 26 cal/mol).From studies of the Raman spectrum at variable temperatures, the conformational enthalpy difference has been determined to be 176 +/- 40 cm-1 (503 +/- 114 cal/mol) and 625 +/- 51 cm-1 (1787 +/- 146 cal/mol) for the gas and liquid, respectively.A complete assignment of the vibrational fundamentals observed from the infrared spectra (3500-50 cm-1) of the gas and solid and the Raman spectra (3200-10 cm-1) of all three physical states is proposed.All of these data are compared to the corresponding quantities obtained from ab initio Hartree-Fock gradient calculations employing both the 3-21G* and 6-31G* basis sets.Additionally, complete equilibrium geometries have been determined for both rotamers.The results are discussed and compared with the corresponding quantities obtained for some similr molecules.
Monoozonides of chloro-substituted conjugated dienes: preparation, stability, and some chemical reactions
Griesbaum, Karl,Bandyopadhyay, Ashis R.,Meister, Martin
, p. 1553 - 1559 (2007/10/02)
The chlorodienes (E)-4-chloro-3-methyl-1,3-hexadiene (5a), (E) and (Z)-4-chloro-2,3-dimethyl-1,3-hexadiene (5b/6b), (E,E)-5-chloro-4-methyl-2,4-heptadiene (5c), (4E)- and (4Z)-5-chloro-3,4-dimethyl-2,4-heptadiene (5d/6d), chloroprene (11a), and 2-chloro-3-methyl-1,3-butadiene (11b) are selectively ozonized at the non-chlorinated double bonds to give the corresponding monoozonides 7, 8, and 12.Further ozonolyzis of the monoozonides of 5b and of 11b in methanol as well as epoxidation of the monoozonide of 5b and subsequent reaction of the resulting chloroepoxide with AgBF4 are described.
Process for the manufacture of polylactones derived from poly-α-hydroxyacrylic acids
-
, (2008/06/13)
Process for the manufacture of polylactones derived from poly-α-hydroxyacrylic acids comprises heating a liquid aqueous solution of α, β-dichloropropionic acid to a temperature above 100°C to convert the α,β-dichloropropionic acid to the corresponding α-chloroacrylic acid and polymerizing the α-chloroacrylic acid in the aqueous solution in the presence of a polymerization catalyst to polymerize, hydrolyze and lactonize the α-chloroacrylic acid. The products obtained can be used as intermediates for the synthesis of salts of poly-α-hydroxyacrylic acids.
