Methoxyacrylates

Methoxyacrylate acaricides are esters of acrylic acid (CH2=CHCOOH). This is a new class of pesticide. Fluacrypyrim is the only member of this class. It is an acaricide for use on fruit. Its oral LD50 in rats is 5000 mg/kg. 

Methyl ( )-2- a-[2-isopropoxy-6-(trifluoromethyl)pyrimidin-4-yloxyl]-o-olyl -3-methoxyacrylate 

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The key step in the total synthesis of rhizobitoxine is the Pd-catalyzed exchange reaction of the methyl alkenyl ether moiety in 4 with the functionalized alcohol, although the yield is low[3]. The enol pyruvate 6 (a-ethoxyacrylic acid) is prepared by the reaction of methyl a-methoxyacrylate or a-methoxy-acrylic acid (5) with ethanol catalyzed by PdCl2(PhCN)2 at room temperature in the presence of CuCli and NaH2P04[4],... 

Methyl ( )-2- 2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]-phenyl -3-methoxyacrylate... 

The addition product of ethyl acetoacetate and methyl a-methoxyacrylate was hydrolyzed, and the resulting dicarboxylic acid was treated with dimethylamine hydrochloride and aqueous formaldehyde. The product of the Mannich reaction was decarboxylated, reesterifed, and finally treated with methyl iodide to supply quaternary salt 469 as the main product. During the above one-pot process, elimination also took place, yielding unsaturated ketone 470, which was later utilized as its hydrogen bromide adduct 471. Reaction of 3,4-dihydro- 3-car-boline either with 469 or 471 furnished the desired indolo[2,3-a]quinolizine derivative 467 as a mixture of two diastereomeric racemates. 

Methoxyacrylates, insecticidal, 14 348 a-Methoxy-a-trifluoromethylphenylacetyl chloride, chiral derivatizing reagent,... 

Strobilurin A, Strobilurin and Myxothiazole new inhibitors of the bci segment of the respiratory chain with an ( )-/l-methoxyacrylate system as common structural elements , FEBS Lett., 1981,132, 329-333. 

J.R. Godwin, V.M. Anthony, J.M. Clough and C.R.A. Godfrey, ICIA5504, A Novel Spectrum, Systemic / -Methoxyacrylate Fungicide , Proceedings of the British Crop Protection Conference - Pests and Diseases , 1992, Vol. 1, pp. 435-442. 

Trifluorovinylstannane has been successfully employed in the Stille crosscoupling reaction with aryl or vinyl halides in the presence of a palladium catalyst [190, 191] (Scheme 68). Recently, ethyl 3-(tributylstannyl)-2-methoxyacrylate was prepared from ethyl trifluoropyruvate in several steps and used in the Stille reaction for the synthesis of a-fluoro-keto acid derivatives [192] (Scheme 69). 

Azoxystrobin (P-methoxyacrylate) is one of 1400 synthesized from the lead compound, strobilurin A. 

Kresoxim-methyl is based on the same strobilurin A lead compounds in which variations of the methoxyacrylate moiety produced the methoxyiminoacetate pharmacophore. 

P-Methoxyacrylates. This is an important class of commercial fungicides based on a group of natural products, the strobilurins (see Fig. 10), such as strobilurin A and oudemansin A. Strobilurins act by inhibition of mitochondrial respiration. In 1996, the first representatives of this class of fungicide were launched, including azoxystrobin [52], In 1999, the first fluorine-containing strobilurin, trifloxystrobin (Flint ) [53], was launched by Syngenta and later acquired by Bayer for 760 million. 

Bromo-6-ethoxy-3-pyridinamine (52) reacted with methyl 3-methoxyacrylate (2 equiv) to give 6-ethoxy-4-methoxy-l-(l-methoxy-2-methoxycarbony-... 

A brief exploration of annulations with nitro-free fluoro arene 37—readily prepared from ( )-methyl 3-methoxyacrylate (36) by a Michael addition elimination strategy with 2-(2-fluorophenyl)acetonitrile (35)—again revealed that direct SNAr cyclization was impeded under all conditions. Extended conjugation may have contributed however, the necessity for the conjugated sp2-hybridized aryl-propene anion to couple intramolecularly with another sp2-hybridized carbon atom imposed a highly strained reaction trajectory (Scheme 9). 

Table 16. Solvent effect on spontaneous polymerizations of methyl a-acetoxyacrylate and methyl a-methoxyacrylate at 60 °C...

These copolymerization parameters are only slightly influenced by the solvent used (Table 18) [116], suggesting a small solvent effect on the propagation reaction. The reactivity of methyl a-methoxyacrylate towards a polystyryl radical (l/r2) however tends to increase with increasing Ex value or dielectric constant of the solvent. Here again it appears that increased solvent polarity leads to an increased persistency of the captodative radical. 

Table 18. Copolymerization parameters for the copolymerization of methyl a-methoxyacrylate (Mi) and styrene (M2) at 60 °C...

The homopolymerization of methyl a-methoxyacrylate is influenced by Lewis acids [116]. Weaker Lewis acids such as ZnCl2 accelerate, but stronger Lewis acids (SnCl4, EtAlCl2, and BF3.OEt2) inhibit both AIBN-initiated and spontaneous homopolymerizations at 25 and 60 °C. 

Fig. 1. Copolymer composition curves for the copolymerization of methyl a-methoxyacrylate and styrene by AIBN in the presence (o) and absence ( ) of ZnCl2 at 60 °C and the polymerization rate in the presence of ZnCl2 (a).

These spectral data support the qualitative experimental results showing the increase of the e-value for the Lewis acid-assisted copolymerization of methyl a-methoxyacrylate [116]. 

These properties, combined with the fact that the second methoxyl group is not attached to the benzene ring and must, therefore, be derived from the dihydroxyphenylalanine (or prephenic acid) precursor, suggest the presence in rhynchophylline of a /3-methoxyacrylic ester residue. Convincing support for this conclusion is provided by a comparison of the UV- and IR-spectra of rhynchophylline with those of appropriate model compounds. Thus, the UV-spectrum of rhynchophylline is identical with the summation spectrum of 3-ethyloxindole and ethyl jS-ethoxy-a-methylacrylate (74), and it is also closely similar to that of formosanine. The IR-absorption of rhynchophylline in the carbonyl region also resembles that of formosanine, except that rhynchophylline exhibits an additional band, of medium intensity, at 1645 cm-1 this band, however, is also present in the spectrum of ethyl jS-ethoxy-a-methylacrylate. 

It is thus apparent that the absorption spectra of rhynchophylline can be explained entirely satisfactorily by the assumption of oxindole and /J-methoxyacrylate chromophores (74). Hence, the alkaloid was provisionally formulated as the oxindole analog of corynantheine or dihydro-corynantheine (56, 74) the resistance to hydrogenation and the Kuhn-Roth determination (0.6 C-Me) are clearly in favor of the latter. 

Allpress and Haworth utilized silver oxide as a condensing agent in the reaction of ethylene glycol with methyl chloroformate, when an imspecified yield of ethylene carbonate was obtained. n-Fructose, under similar treatment, was severely degraded— to 1-methoxyacrylic acid. 

Reaction of 3-mercapto-2-butanone with 3-methoxyacrylate in the presence of NaOMe gives tetrahydrothiophene 471 via intramolecular cyclization of the intermediate 470. Compound 471 is converted into thiophene 472 by treatment with HCl (Scheme 78) <2001JOC2493>. Its cost-effective and scaleable synthesis is also reported <20020PD357>. 

Inhibitors binding at the Qo site exclusively to cytochrome b, e.g., myxothiazol as well as E-fi-methoxyacrylate (MOA) and related inhibitors. These inhibitors prevent the reduction of both the Rieske center and heme 6l through die Qo site but heme hn can still be reduced through the Qi site with hydroquinone acting as a reductant (reverse electron flow). 

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