Complex-bonded and continuously generated peroxy and alkoxy radicals

1975 ◽  
Vol 40 (1) ◽  
pp. 117-128 ◽  
Author(s):  
A. Tkáč ◽  
K. Veselý ◽  
L. Omelka ◽  
R. Přikryl
Keyword(s):  
Alkoxy Radicals

Fragmentation of alkoxy radicals: Synthesis of macrolactones by sequential ring expansion reactions

1994 ◽  
Vol 35 (40) ◽  
pp. 7463-7466 ◽  
Author(s):  
Teresa Arencibia ◽  
José A. Salazar ◽  
Ernesto Suárez
Keyword(s):  
Ring Expansion ◽  
Alkoxy Radicals

Fragmentation of carbohydrate anomeric alkoxy radicals: a new synthesis of chiral 1-halo-1-bromo compounds

2003 ◽  
Vol 44 (33) ◽  
pp. 6347-6350 ◽  
Author(s):  
Concepción C González ◽  
Elisa I León ◽  
Concepción Riesco-Fagundo ◽  
Ernesto Suárez
Keyword(s):  
Alkoxy Radicals ◽  
New Synthesis

Atmospheric fate of alkoxy radicals: branching ratio of evolution pathways for 1-propoxy, 2-propoxy, 2-butoxy and 3-pentoxy radicals

2003 ◽  
Vol 5 (21) ◽  
pp. 4834 ◽  
Author(s):  
N. Meunier ◽  
J. F. Doussin ◽  
E. Chevallier ◽  
R. Durand-Jolibois ◽  
B. Picquet-Varrault ◽  
...  
Keyword(s):  
Branching Ratio ◽  
Alkoxy Radicals ◽  
Atmospheric Fate

ChemInform Abstract: REACTIONS OF ALKOXY RADICALS IN AQUEOUS SOLUTIONS

1984 ◽  
Vol 15 (28) ◽  
Author(s):  
W. BORS ◽  
D. TAIT ◽  
C. MICHEL ◽  
M. SARAN ◽  
M. ERBEN-RUSS
Keyword(s):  
Aqueous Solutions ◽  
Alkoxy Radicals

Alkoxy Radicals See the Light: New Paradigms of Photochemical Synthesis

2021 ◽  
Author(s):  
Liang Chang ◽  
Qing An ◽  
Lingfei Duan ◽  
Kaixuan Feng ◽  
Zhiwei Zuo
Keyword(s):  
Photochemical Synthesis ◽  
Alkoxy Radicals

Radical Mechanisms in Saturated and Olefinic Systems. II. Disubstitutive Carbon-Carbon Cross-Linking by Tertiary Alkoxy Radicals in Isoprenic Olefins and Rubber

1951 ◽  
Vol 24 (4) ◽  
pp. 777-786
Author(s):  
E. H. Farmer ◽  
C. G. Moore
Keyword(s):  
Natural Rubber ◽  
Cross Linking ◽  
Chain Molecules ◽  
Alkoxy Radicals ◽  
Full Extent ◽  
Carbon Chains ◽  
Butyl Peroxide ◽  
High Degree ◽  
Vulcanization Process

Abstract The high degree of dehydrogenation effected by tert.-butoxy radicals at the α-methylenic groups of olefins enables these radicals to be used for the carbon-to-carbon cross-linking of unsaturated carbon chains, and especially of the polyisoprenic chains of natural rubber. Such cross-linking amounts to a vulcanization process in which the connecting links between chain molecules are just C—C bonds, which may be expected to have appropriate attributes. An examination has first been made of the cross-linking produced by tert.- butoxy radicals (from di-tert.-butyl peroxide) at 140° between the short iso-prenic chains in 1-methylcyclohexene, 4-methylhept-3-ene, 2,6-dimethylocta-2, 6-diene, and digeranyl. Cross-linking proceeds efficiently in each case, and the points of union in these isoprene units which become directly joined are not confined to original α-methylenic carbon atoms. Where the reagent radicals are in considerable deficit, e.g., one per two or three of the isoprene units present, those olefin molecules which are attacked become linked together mostly by single unions to form aggregates containing two, three or four molecules; but in the tetraisoprenic olefins the extent to which more than one union is formed between some of the directly linked molecules becomes appreciable. In natural rubber, cross-linking occurs smoothly and to nearly the full extent corresponding to the (in practice restricted) proportion of peroxidic reagent employed. Good vulcanizates can be so obtained in which the tensile stength is found to increase towards a maximum and then to decline rapidly as the degree of cross-linking steadily increases. Thus to obtain vulcanizates of the optimum physical characteristics, the degree of cross-linking must be suitably chosen. The role of the peroxidic reagent is almost entirely non-additive and non-degradative.

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