Acetylenic compounds, synthesis

Acetonitrile, 407 Acetophenone, 725,729,730 phenylhydrazone, 852 p-Acetotoluidide, 593, 605 Acetoxime, 343 Acetylacetone, 861, 862, 863 Acetylation, reductive, 749 Thiele, 749 Acetyl chloride, 367 2-Acetylcyciohexanone, 862, 864 Acetylene, 245, 897 reactions of, 245, 246 Acetylenic compounds, synthesis of, 467-469, 895-902 Acetylglycine, 909 Acetylmethylurea, 968, 969 Acetylsalicylio acid, 996 Acetyl-o-toluidide, 578 2-Acetylthiophene, 837 Acid anhydrides of aliphatic carboxylic acids, 371... 

Compounds containing a double or triple bond, usually activated by additional unsaturation (carbonyl, cyano, nitro, phenyl, etc.) In the ap position, add to the I 4-positions of a conjugated (buta-1 3-diene) system with the formation of a ax-membered ring. The ethylenic or acetylenic compound is known as the dieTwphile and the second reactant as the diene the product is the adduct. The addition is generally termed the Diels-Alder reaction or the diene synthesis. The product in the case of an ethylenic dienophile is a cyctohexene and in that of an acetylenic dienophile is a cyctohexa-1 4-diene. The active unsaturated portion of the dienophile, or that of the diene, or those in both, may be involved in rings the adduct is then polycyclic. 

Raphael, Acetylenic Compounds in Organic Synthesis, 1955 (Butterworths). 

R.A. Raphael, "Acetylenic Compounds in Organic Synthesis", Butterworths Scientific Publications, London, (1955). 

An unusual and different use of an aryldifluorovinyllithium compound is the synthesis of acetylenic compounds containing no fluorine [65] (equation 32)... 

Cycloaddition of diazoindazole 376 with acetylenic compounds afforded (77S556 78CB2258) triazinoindazoles 377. The synthesis of the diaza analogue of 377 was also successful (Scheme 83). 

The state of research on the two classes of acetylenic compounds described in this article, the cyclo[ ]carbons and tetraethynylethene derivatives, differs drastically. The synthesis of bulk quantities of a cyclocarbon remains a fascinating challenge in view of the expected instability of these compounds. These compounds would represent a fourth allotropic form of carbon, in addition to diamond, graphite, and the fullerenes. The full spectral characterization of macroscopic quantities of cyclo-C should provide a unique experimental calibration for the power of theoretical predictions dealing with the electronic and structural properties of conjugated n-chromophores of substantial size and number of heavy atoms. We believe that access to bulk cyclocarbon quantities will eventually be accomplished by controlled thermal or photochemical cycloreversion reactions of structurally defined, stable precursor molecules similar to those described in this review. 

Whiting Researches on Acetylenic Compounds. Part XXXIV. Further Studies on the Synthesis of Diacetylenic Glycols. J. Chem. Soc. [London] 1952, 1998. 

Studies related to Naturally Occurring Acetylene Compounds. VII. The Synthesis of two Stereoisomers of Methyl n-Decadiene-2,8-diyn-4,6-oates the Configuration of Matricaria Ester. Acta Chem. Scand. 5, 1244 (1951). 

Occurring Acetylene Compounds. VIII. The Synthesis of Methyl n-Dec-2-en-4 6 8-triynoate, an Isomer of the Naturally Occurring Dehydro-matricaria Ester. Acta Chem. Scand. 6, 602 (1952). 

Studies Related to Naturally Occurring Acetylene Compounds. XXX. The Synthesis of 5-Methyl-5 -(buta-l,3-dienyl)-2,2 -bithienyl. Acta Chem. Scand. 15, 2047 (1961). 

Occurring Acetylene Compounds. XXVII. The Synthesis of a Mixture of Trideca-1.3,1l-triene-5,7,9-triyne (II) and trans-l-Phenylhepta-l,3-diyn-5-ene (V). A Novel Cyclisation Reaction. Acta Chem. Scand. 13, 2101 (1959). 

Cross-coupling of terminal acetylenes used as nucleophiles with aryl or alkenyl halides (referred to as the Sonogashira-Hagihara, or SH, reaction) is a versatile method of synthesis for acetylenic compounds, which are rapidly gaining importance as advanced new materials and building blocks for implementing unusual molecular architectures. 

Acetylenic compounds and acetylenic organotin compounds are widely used in the synthesis of many organostannane derivatives of importance in further synthetic procedures. 

The present procedure9 represents another synthesis of cyelobutanone through the unique acetylenic bond participation in solvolysis. Cyclobutane derivatives prepared in this way include 2-methyl-, 2-ethyl-, 2-isopropyl-, and 2-trifluoromethylcyclobutanone from the corresponding acetylenic compounds.10... 

Sodium amide has been extensively used in the synthesis of a large number of acetylenic compounds by dehydrohalogenation. An example is ... 

Lithium amide is used in synthesis of histamine and analgesic drugs. The compound also is used in many organic synthetic reactions including alkylation of ketones and nitriles, Claisen condensation, and in synthesis of antioxidants and acetylenic compounds. 

R.A. Raphael," Acetylenic Compounds in Organic Synthesis" Butterworths, 1955. 

The rearrangement occurs more readily when activating groups (aryl, carboxyl, etc.) are attached to the triple bond. Jacobs [38] reports that a reaction involving adsorption of an acetylenic compound on an active basic surface has led to the practical synthesis of arylallenes, allenyl ethers, allenyl halides, and other substituted allenes. 

Acetylenic compounds may in some cases be suitable sources of 1,3-dioxo precursors as shown for propynal in the synthesis of 85a-d.62,l27 131 Similarly, the preparation of probable 4//-pyran derivative 91 (61.7%) may be explained by a hydration catalyzed with Zn2+ ions, which leads to a 1,5-dicarbonyl intermediate.138... 

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