| 单词 | ketene | 
| 释义 | ketenen. Chemistry.  a.  Any compound containing an ethylenic double bond adjacent to a carbonyl group, i.e. the structure C=C=O. ΚΠ 1905    Jrnl. Chem. Soc. 88 444  				Diphenylketen CPh2:CO, the first representative of a new type of compound, is prepared by the action of zinc on an ethereal solution of diphenylchloroacetyl chloride.]			 1907    Jrnl. Chem. Soc. 91 1941  				There can..be no doubt that the new substance is a keten, having the formula CH2:CO. 1942    R. C. Fuson  & H. R. Snyder Org. Chem. xxi. 296  				Carbonyl compounds which contain the grouping C=C=O are known as ketenes... Ketenes fall into two classes, aldoketenes and ketoketenes. 1971    Jrnl. Chem. Soc. (C) 3645  				The addition of ketenes to conjugated dienes generally yields 1,2-adducts.  b.  The simplest of the ketenes, CH2:C:O, a pungent colourless gas which dimerizes on liquefaction and has wide applications in synthesis owing to its high reactivity. ΚΠ 1907    Jrnl. Chem. Soc. 91 1941  				Keten has a peculiar penetrating smell. 1907    N. T. M. Wilsmore  & A. W. Stewart in  Nature 75 510/1  				We would suggest that the body is the parent substance of Staudinger's ketenes. 1907    N. T. M. Wilsmore in  Jrnl. Chem. Soc. 91  ii. 1939  				The keten series. 1911    Encycl. Brit. XV. 761/2  				Two classes may be distinguished: the aldo-ketenes, including ketene itself,..and the keto-ketenes. 1946    Nature 19 Oct. 553/2  				Believing that the usual methods of acetylation give degraded products, Wassermann has attempted to acetylate alginic acid with ketene. 1964    N. G. Clark Mod. Org. Chem. xi. 211  				On heating acetic acid vapour at 700° to 800° under reduced pressure, it loses the elements of water to form keten. 1972    Guardian 16 Oct. 15/2  				Although keten and its organic relations have been known and used for generations, no one had realised that they could produce salts. This entry has not yet been fully updated (first published 1933; most recently modified version published online December 2020). <  | 
	
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