Acetylenic esters properties

Acetylenecarboxylic esters, reactions with nitrogen-containing heterocycles, 23, 263 Acetylenic derivatives of pyrazoles, synthesis and properties of, 82, 1 Acetylenic esters, synthesis of heterocycles through nucleophilic additions to, 19,297 Acid-catalyzed polymerization of pyrroles and indoles, 2, 287... 

Photoaddition of dimethyl acetylenedicarboxylate to cis- and trans-but-2-enes gives four [(76), (77), (78), and (79) E = C02Me] of the seven possible bicyclic products. The structures of the adducts were established by 220 MHz n.m.r. spectroscopy and by consideration of the symmetry properties of the molecules. The acetylenic ester is the excited partner in the addition. Under the conditions described, no mono-adducts could be detected in the products. 

Room temperature conditions affected only the conversion, the reaction rate being smaller (entry 6). Noticeably, cyclization of 2-prop-2-ynyl-malonic acid monomethyl ester le and 2-phenyl-pent-4-ynoic acid If, also occurred with very good results (entries 7, 8). The obtained results may be ascribed to the LDH support, which exhibits enough basic properties to activate the unsubtituted acetylenic carboxylic acids. Basically, the composition of the LDH exhibits only a very minor influence in these reactions. 

Most acetylenic compounds in plants are derived from meta-bolically altered fatty acids. These often are active in plant-insect relationships. 8-cis-Dihydromatricaria acid is also found in the defensive secretion of the soldier beetle (Chaulioqnathus 1econtei) (125), and has subsequently been shown to have anti-feedant properties against Phidippus spp. (jumping spiders) (126). As previously mentioned matricaria ester has antifeedant properties to the pink bollworm, bollworm and tobacco budworm (115). 

Syntheses and properties of acetylenic derivatives of pyrazoles 02AHC(82)1. Syntheses of 2-pyrazolines by the reactions of a,/ -unsaturated aldehydes, ketones, and esters with diazoalkanes, nitrile imines, and hydrazines 02JHC1. 

The preparation, properties, and reactions, especially polymerization, of products from the acetylene-carbon monoxide reaction, such as acrylic acid and its esters, are given by Blout and Mark (8) and by Schildknecht (98). Similarly treated therein are the vinyl esters from acetylene and carboxylic acids, and other vinylation products such as vinyl ethers. The esterification of organic acids with olefins is reviewed by Morin and Bearse (76). 

Maier, L., Organic phosphorus compounds. Part 58. Preparation and properties of acetylene diphos-phonates, haloethene-l,2-diphosphonates, and the corresponding acids. Phosphorus, 2, 229, 1973. Garibina, V.A., Dogadina, A.V., Zakharov, V.I., lonin, B.I., and Petrov, A.A., (Haloethynyl)phospho-nates. Synthesis and electrophihc reactions of (chloroethynyl)phosphonic esters, Zh. Obshch. Khim., 49, 1964, 1979 J. Gen. Chem. USSR (Engl. Transl.), 49, 1728, 1979. 

Silyl ynol ethers have highly characteristic spectral properties. The triple bond stretching in the IR of siloxyalkynes is at 2260-2270 cm" which compares with that of ynol esters and alkoxyacetylenes (see Sections III and IV of the present review) ". Particularly noteworthy and characteristic are the acetylenic carbon signals in the NMR. The... 

Alkoxyalkynes have characteristic spectral properties . The triple bond stretching in the IR of alkoxyacetylenes varies from 2290 cm in 1-ethoxyhexyne to 2130-2160 cm in the parent" " and silylated" alkoxyethynes. The signals of both acetylenic carbons in the NMR are located in the normal alkyne region of 80-90 ppm f , which is distinctly different from siloxyacetylenes (see Section II.D.l) and ynol esters (Section IV.B). The mass spectra of alkoxyacetylenes almost always have a peak for the molecular ion and easily identifiable, characteristic fragmentation" " . ... 

The addition of azides to acetylenic acids or esters has been used with good results (Eqs. 29 to 32). The ease with which these acids decarboxylate is indicated by the presence of 4-2-8 in Equation 29. This property has been useful in many structure proof problems (e.g.. Reference 2). An interesting variant of this approach involves the lotsich complexes (e.g., 4.2-9) (Eq. 33). ... 

Cobalt, nickel, iron, ruthenium, and rhodium carbonyls as well as palladium complexes are catalysts for hydrocarboxylation reactions and therefore reactions of olefins and acetylenes with CO and water, and also other carbonylation reactions. Analogously to hydroformylation reactions, better catalytic properties are shown by metal hydrido carbonyls having strong acidic properties. As in hydroformylation reactions, phosphine-carbonyl complexes of these metals are particularly active. Solvents for such reactions are alcohols, ketones, esters, pyridine, and acidic aqueous solutions. Stoichiometric carbonylation reaction by means of [Ni(CO)4] proceeds at atmospheric pressure at 308-353 K. In the presence of catalytic amounts of nickel carbonyl, this reaction is carried out at 390-490 K and 3 MPa. In the case of carbonylation which utilizes catalytic amounts of cobalt carbonyl, higher temperatures (up to 530 K) and higher pressures (3-90 MPa) are applied. Alkoxylcarbonylation reactions generally proceed under more drastic conditions than corresponding hydrocarboxylation reactions. 

Lermontov et al. reported some successful reactions of two a,a-difluoroazides, namely, 2-hydroperfluoropropyl azide and the methyl ester of 3-azido-perfluoropropanoic acid, with various acetylene compounds, and described some properties of the resulting products [45], Thus, phenylacetylene reacts with 2-hydroperfluoropropyl azide to give the corresponding 4-phenyl-l-(2H-perfluoropropyl)- ,2,3-triazole 41 and 5-phenyl-l-(2H-perfluoropropyl)-l,2,3-triazole 42 in 1/2 ratio. Disubstituted acetylenes also react with these azides to give the corresponding lH-1,2,3-triazoles [45]. Thus in the case of triazole 43 the yield is close to the quantitative. 

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