Allylene

Synonyms Allylene BRN 0878138 CCRIS 6830 EINECS 200-828-4 Methyl acetylene Propine 1-Propyne. 

Acetylenic Compounds are organic compounds contg at least one triple bond -O C-. They may be hydrocarbons, alcohols, acids, aldehydes, etc. The acetylenic hydrocarbons include, in addition to acetylene (qv), the higher members, such as allylene or propyne H,CC s CH, crotonylene or butyne -2 HjCC i C.CHj, valerylene or pentyne - 2 H, C2.C C.CH, etc... 

Reaction XXXIV. (c) Action of Carbon Dioxide on Sodium Acetylides in Dry Ether. (B., 12, 853 J. pr., [2], 27, 417 B., 33, 3586.)—This is an example of the great activating influence of a triple bond. When carbon dioxide is passed into a solution of the sodium derivative of an acetylenic hydrocarbon in dry ether, direct addition takes place to give the sodium salt of the next highest acetylenic carboxylic acid. For example, sodium allylene yields sodium tetrolate—... 

Acetylene is converted to acetaldehyde, allylene to acetone, and valerylene also to a ketone ... 

Favored configurations for the 2-(dimethylene)allylene system 4 were sought through calculations in which the dihedral angles a for HC(3)C(2)C(5), P for C(4)C(5)C(2)C(3), and y for HC(4)C(5)C(2) were systematically varied. The geometrical parameters employed were... 

Table 1. Calculated energies for conformation isomers of 2-(dimethylene) allylene 4...

For the allene-olefin system, orbital symmetry controls the stereochemistry leading to the 2-(dimethylene) allylene intermediate as though the reaction were to be an energetically concerted Jt2s + ji2s + process,... 

The molecular orbital calculations for the 2-(dimethylene)allylene system discussed above did not give a minimum energy through varying many geometrical parameters thus the optimum geometry for 4 (0,90,90) is still very much an open question. 

SYNS ACETYLENE, METHYL- ALLYLENE PROPINE PROPYNE (OSHA)... 

ALLYLE (CHLORURE d) (FRENCH) see AGB250 ALLYL ENANTHATE see AGH250 ALLYLENE see MFX590... 

Fe2(C0)fl at 50°C under pressure produces, in addition to this same 7T-allylene complex, the o-.Tr-allyl complex (CaH4)Fe2(CO)7 (66) (58,156). 

Methylacetylene (Allylene, Propyne). CHsChCH, mw 40.07, colorl liquified gas bp —23.1°, fr p -101.5° flammable, dangerous fire and expl risk. It is self-reactive, and can decomp explosively at 4.5 to 5.6 atms press (Ref 2). An expln occurred at Dow s Freeport, Texas plant in 1960 while workers were loading a small tank of methyl acetylene. Following this expln, a 2000 gal tank blew up and burned for IM hours. The cause of the blasts were not detd (Ref 1)... 

Propargyl Alcohol.—Only one alcohol of this series will be considered. The simplest primary alcohol possible derived from hydrocarbons of the acetylene series is the one derived from allylene, CH = C—CH3, methyl acetylene. 

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