83559-38-0Relevant articles and documents
Room temperature acylketene formation 1,3-dioxin-4-ones via silver(I) activation of phenylthioacetoacetate in the presence of ketones
May, Aaron E.,Hoye, Thomas R.
supporting information; experimental part, p. 6054 - 6056 (2010/11/03)
Silver(I) activation of thioacetoacetates in the presence of ketones produces 1,3-dioxin-4-ones. Mechanistic studies addressing the intermediacy of an acylketene intermediate are described.
Enantioselective Synthesis of Spiro Ethers and Spiro Ketals via Photoaddition of Dihydro-4-pyrones to Chiral 1,3-Dioxin-4-ones 1
Haddad, Nizar,Rukhman, Igor,Abramovich, Zehavit
, p. 7629 - 7636 (2007/10/03)
A versatile and highly stereoselective synthesis of spiro ethers and spiro ketals is presented. The key step in the developed synthetic sequence is based on diastereoselective intramolecular photoaddition of dihydro-4-pyrones to chiral 1,3-dioxin-4-ones. Subsequent fragmentation of the produced four-membered ring provides spiro ether structures. The spiro ethers can be transformed to their corresponding spiro ketals, with retention of configuration at the spiro center, via Baeyer-Villager oxidation. The configuration of the spiro center is defined by the facial selectivity at the photocycloaddition step. Two examples of complete stereofacial selectivity were achieved. The unique and important application of the developed sequence was demonstrated in enantioselective synthesis of a less thermodynamically stable spiro ketal 43.
Onium Salt-Catalyzed Reactions between Carbonyl Compounds and Diketene
Dehmlow, Eckehard V.,Shamout, Abdul Rahman
, p. 1753 - 1755 (2007/10/02)
4-Oxo-1,3-dioxins (plus dehydracetic acid) are obtained in high yields on refluxing the title compounds in toluene in the presence of catalytic amounts of quaternary ammonium chlorides.