Li, Shuangqing; Wang, Shuangshuang; Li, Juan; Qi, Yue; Wang, Chao; Zong, Lili; Tan, Choon-Hong published an article in 2021. The article was titled 《Monocationic Cinchoninium Catalyzed Asymmetric Oxohydroxylation of Enoates》, and you may find the article in ACS Catalysis.Electric Literature of C9H10O2 The information in the text is summarized as follows:
In this paper, asym. oxohydroxylation of α-alkyl enoates RCH=C(R1)C(O)OR2 (R = Me, cyclohexyl, furan-2-yl, etc.; R1 = Me, prop-2-en-1-yl, prop-2-yn-1-yl, Bn, etc.; RR1 = -(CH2)3-, -(CH2)4-; R2 = Et, Bn, 2-(4-methoxyphenyl)-2-oxoethyl) with potassium permanganate catalyzed by monocationic quaternary ammonium salts I (R3 = H, Bn, (2-bromo-3,5-di-tert-butylphenyl)methyl, [3,5-bis(3,5-di-tert-butylphenyl)phenyl]methyl, etc.; R4 = Br, F, CF3; R5 = F, CF3, [3,5-bis(trifluoromethyl)phenyl]methyl) derived from cinchona alkaloid is reported. A series of α-hydroxy-β-keto esters RC(O)C(R1)(OH)C(O)OR2 were obtained in up to 96% yield and 98% ee under user-friendly conditions. Synthetic application of oxohydroxylation was demonstrated in the synthesis of key chiral building blocks for thapsigargin and camptothecin synthesis. Control experiments indicated that, compared with tetrabutylammonium, monocationic chiral cinchoninium has a dramatic rate acceleration effect on catalytic permanganate oxidation After reading the article, we found that the author used 2-(Benzyloxy)acetaldehyde(cas: 60656-87-3Electric Literature of C9H10O2)
2-(Benzyloxy)acetaldehyde(cas: 60656-87-3) is a non-natural aldehyde. It undergoes enantioselective Mukaiyama aldol reaction with silylketene acetal nucleophiles in the presence of C2-symmetric bis(oxazolinyl)pyridine Cu(II) complex (catalyst).Electric Literature of C9H10O2
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem