Photochemical Cleavage and Release of Para-Substituted Phenols from α-Keto Amides was written by Ma, Chicheng;Chen, Yugang;Steinmetz, Mark G.. And the article was included in Journal of Organic Chemistry in 2006.Product Details of 1877-75-4 This article mentions the following:
In aqueous media α-keto amides 4-YC6H4OCH2COCON(R)CH(R’)CH3 (5a, R = Et, R’ = H; 5b, R = iPr, R’ = Me) with para-substituted phenolic substituents (Y = CN, CF3, H) undergo photocleavage and release of 4-YC6H4OH with formation of 5-methyleneoxazolidin-4-ones 7a,b. For both 5a,b quantum yields range from 0.2 to 0.3. The proposed mechanism involves transfer of hydrogen from an N-alkyl group to the keto oxygen to produce zwitterionic intermediates 8a–c that eliminate the para-substituted phenolate leaving groups. The resultant iminium ions H2C:C(OH)CON+(R):C(R’)CH3 9a,b cyclize intramolecularly to give 7a,b. The quantum yields for photoelimination decrease in CH3CN, CH2Cl2, or C6H6 due to competing cyclization of 8a,b to give oxazolidin-4-one products which retain the leaving group 4-YC6H4O– (Y = H, CN). A greater tendency to undergo cyclization in nonaqueous media is observed for the N,N-di-Et amides 5a than the N,N-diisopropyl amides 5b. With para electron releasing groups Y = CH3 and OCH3 quantum yields for photoelimination significantly decrease and 1,3-photorearrangement of the phenolic group is observed The 1,3-rearrangement involves excited state ArO-C bond homolysis to give para-substituted phenoxyl radicals, which can be observed directly in laser flash photolysis experiments In the experiment, the researchers used many compounds, for example, 2-(4-Methoxyphenoxy)acetic acid (cas: 1877-75-4Product Details of 1877-75-4).
2-(4-Methoxyphenoxy)acetic acid (cas: 1877-75-4) belongs to ethers. Ether is less polar than esters, alcohols or amines because of the oxygen atom that is unable to participate in hydrogen bonding due to the presence of bulky alkyl groups on both sides of the oxygen atom. But ether is more polar than alkenes. Autoxidation is the spontaneous oxidation of a compound in air. In the presence of oxygen, ethers slowly autoxidize to form hydroperoxides and dialkyl peroxides. If concentrated or heated, these peroxides may explode. To prevent such explosions, ethers should be obtained in small quantities, kept in tightly sealed containers, and used promptly.Product Details of 1877-75-4
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem