Collect. Czech. Chem. Commun.
1996, 61, 1053-1063
https://doi.org/10.1135/cccc19961053
Alkoxycarbonylation of Alcohols and Phenols by Nitrosoformates
Jaromír Mindla, Aleš Halamaa and Zdeněk Černošekb
a Department of Organic Chemistry, University of Pardubice, 532 10 Pardubice, Czech Republic
b Department of General and Inorganic Chemistry, University of Pardubice, 532 10 Pardubice, Czech Republic
Abstract
Unstable neutral radicals [ROCONHOU.] 2 and nitrosoformates 3 are formed by oxidation of N-hydroxycarbamates with lead dioxide. In the presence of alcohols or phenols and water they solvolyzed to mixtures of symmetrical 4 and asymmetrical 5 carbonates. The content of asymmetrical carbonates 5 increases with increasing reactivity of the nitrosoformates 3 formed, temperature, the content of water in the reaction mixture, and with decreasing reactivity of alcohol. The reactivities of individual alcohols have been evaluated with the help of competitive alcoholysis. The new method of alcohol or phenol alkoxylation has been verified experimentally by preparing six asymmetrical carbonates which were obtained in 34 to 47% yields.
Keywords: Lead dioxide; Hydroxycarbamates oxidation; Carbonates, preparation by alkoxycarbonylation; Alcohols; Alkoxycarbonylation; Phenols, alkoxycarbonylation.