Über das Auftreten freier Radikale bei chemischen Reaktionen. IX

Abstract

Beim thermischen Zerfall von Triphenylmethyl-azoverbindungen (C,H,), C.N = N.R, wobei R Aryl oder 10

Radical Substitution In Aromatic Nuclei

“…Little formation of carbon dioxide and none of any biaryl or (CeHs^CAr was observed. Exclusively para substitution was noted (410,412).…”

“…Only two isolated examples of nuclear acylation have been interpreted as involving radicals. The thermal reaction of either benzoyltriphenylmethyldiimide (409), C6HbCON=NC(C6H5)3, or /3-benzopinacolone (412), C6HbCOC(C6H6)3, yields 4-triphenylmethylbenzophenone in a rearrangement probably analogous to the noncyclizing disproportionation of triphenylmethyl itself. It is ventured here that the Fries-like rearrangement of phenolic esters such as phenyl cyclohexanecarboxylate and phenyl 3-methyl-2-butanoate into o-hydroxy ketones,…”

Quantitative Investigation of Homolytic Arylation

“…References: ^omberg (1900); 2 Hodgson and Marsden (1940); 3 Grieve and Hey (1934); 4 Elks and Hey (1943); 5 Grieve and Hey (1932); 6 Case (1938); 7 France, Heilbron and Hey (1938); 8 Elks, Haworth and Hey (1940); 9 Hey and Lawton (1940); 10 Hey (1934); n Butterworth, Heilbron, Hey and Wilkinson (1938); 12 Heilbron, Hey and Wilkinson (1938); 13 Gomberg and Pernert (1926); 14 Möhlau and Berger (1893b); 15 Wieland, Popper and Seefried (1922); ie Bamberger (1895); 17 Bamberger (1896); 18 Franc^ Heilbron and Hey (1939); 19 Kliegl and Huber (1920); 20 Kuhling (1895Kuhling ( , 1896; 21 Dietrich (1925); 22 Lippmann (1886); 23 Hey (1932); 24 Dunstan and Hughes (1946); 25 Harley-Mason and Mann (1940); 26 Gomberg and Bachmann (1924); 27 Hey and Walker (1948); 28 Haworth, Heilbron and Hey (1940a); 29 Haworth, Heilbron and Hey (1940b); 30 Wieland and co-workers (1930Wieland and co-workers ( , 1934...…”

Homolytic Aromatic Arylation

“…The addition of some metals to the reaction mixture has been shown (284) to result in the formation of metallic chlorides or organometallic compounds, even in slightly alkaline media, and this demonstrates the existence of the highly reactive radicals. Clearly, the reactions of diazo compounds (267), l-aryl-3,3-dialkyltriazenes (111), arylazotriarylmethanes (159, 181, [293][294][295][296][297], and stabilized diazonium compounds (181) are analogous.…”