ABSTRACT
4-Acyl-1-hydroxy-2,3-benzodioates were regioselectively prepared by chelation-controlled [3+3] cyclization of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-acyl-4-ethoxy-2-oxo-3-enoates.
Subject(s)
Benzoates/chemistry , Benzoates/chemical synthesis , Butadienes/chemistry , Butyrates/chemistry , Chelating Agents/chemistry , Nitro Compounds/chemistry , Cyclization , Esters/chemistry , Stereoisomerism , Substrate SpecificityABSTRACT
4-Hydroxy-4-(pyridyl)alk-3-en-2-ones were prepared by base-mediated condensation of ketones with pyridinecarboxylates. Several derivatives show weak antimicrobial activity against Gram-positive and Gram-negative bacteria.
Subject(s)
Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Bacillus subtilis/drug effects , Escherichia coli/drug effects , Ketones/pharmacology , Pyridines/chemical synthesis , Pyridines/pharmacology , Staphylococcus aureus/drug effects , Bacillus subtilis/growth & development , Escherichia coli/growth & development , Ketones/chemical synthesis , Ketones/chemistry , Pyridines/chemistry , Staphylococcus aureus/growth & developmentABSTRACT
1-Hydroxy-3,5-dimethyl-2,4-benzodioates (4-hydroxyisophthalates) were prepared by [3+3] cyclocondensation of 1,3-bis(silyloxy)-1,3-butadienes with 3-ethoxycarbonyl-4-trimethylsilyloxy-3-penten-2-one which is synthesized from (symmetrical) ethyl 2-acetylacetoacetate. The [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 3-alkoxy-2-alkoxycarbonyl-2-en-1-ones, readily available by reaction of beta-ketoesters with trialkyl orthoformiates, provide a convenient and regioselective approach to a great variety of 3-substituted 1-hydroxy-2,4-benzodioates that are not readily available by other methods.
Subject(s)
Alcohols/chemistry , Butadienes/chemistry , Catalysis , Bridged Bicyclo Compounds/chemistry , Cyclization , Hydrogenation , Silanes/chemistry , StereoisomerismABSTRACT
The formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with readily available 2-arylsulfonyl-3-ethoxy-2-en-1-ones resulted in regioselective formation of 4-(arylsulfonyl)phenols.
ABSTRACT
6-(Thien-2-yl) and 6-(fur-2-yl)salicylates are prepared by TiCl(4)-mediated [3 + 3] cyclocondensations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-(thien-2-yl)- and 3-(fur-2-yl)-3-silyloxy-2-en-1-ones, respectively. The regioselectivity of the cyclization depends on the substitution pattern of the 3-silyloxy-2-en-1-one.
