22524-02-3Relevant articles and documents
Synthesis of novel 5-alkyl/aryl/heteroaryl substituted diethyl 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates by aziridine ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters
More, Satish S.,Mohan, T. Krishna,Kumar, Y. Sateesh,Kumar, U.K. Syam,Patel, Navin B.
scheme or table, p. 831 - 838 (2011/08/10)
A novel synthetic methodology has been developed for the synthesis of diethyl 5-alkyl/aryl/heteroaryl substituted 3,4-dihydro-2H-pyrrole-4,4- dicarboxylates (also called 2-substituted pyrroline-4,5-dihydro-3,3-dicarboxylic acid diethyl esters) by iodide i
Efficient synthesis of 4-ethoxycarbonyl pyrazolin-5-one derivatives
Jung, Jae C.,Watkins, E Blake,Avery, Mitchell A.
, p. 3767 - 3777 (2007/10/03)
Concise and efficient methods for the preparation of 3-substituted 4-ethoxycarbonylpyrazolin-5-ones are described. The synthetic strategies involve carbon-acylation in the presence of base, followed by ring cyclization with hydrazine or hydrazine monohydrochloride.
Procedures for the Acylation of Diethyl Malonate and Ethyl Acetoacetate with Acid Chlorides Using Tertiary Amine Bases and Magnesium Chloride
Rathke, Michael W.,Cowan, Patrick J.
, p. 2622 - 2624 (2007/10/02)
In the presence of magnesium chloride and 2 equiv of triethylamine, diethyl malonate is C-acylated in excellent yields by acid chlorides.A variety of other metal chlorides were ineffective.Similarly, ethyl acetoacetate is C-acylated by acid chlorides in the presence of magnesium chloride and 2 equiv of pyridine.
Malonate Anion Induced Favorskii Type Rearrangement. 21. Reaction of Acyclic α-Halo Ketones with Carbanions Leading to Cyclopropanols2
Sakai, Takashi,Katayama, Tsuyoshi,Takeda, Akira
, p. 2924 - 2931 (2007/10/02)
The reaction of 3-bromo-3-methyl-2-butanone (6a) with ethyl sodiomalonate (2) in refluxing THF gave 1--2,2-dimethylcyclopropanol (9a), the Favorskii-type intermediate, in 51percent yield.Similar reactions of acyclic halo ketones such as 2-bromo-2-methyl-3-pentanone (6b), 1-acetyl-1-bromocyclohexane (6c), and 1-acetyl-1-bromocyclopentane (6d) with 2 also gave the corresponding cyclopropanols 9b-d in 42-56percent yields.On the contrary, the α-halo ketones (6f-l) possessing a primary or secondary carbon atom at the α position afforded the SN2 products10f-l.The behavior of 3-chloro-3-methyl-2-butanone (6e) was quite different from that of its bromo homologue 6a, giving a mixture (16:45:39) of 9a, 1,1-bis-2,2-dimethylcyclopropane (14), and 1--2,2-dimethyl-1-cyclopropane (15) in 75percent total yield.Hydrolysis of 9a with 0.2 N NaOH at room temperature gave the acid ester 18, which afforded a mixture of 3-carboxy-4,5,5-trimethyl-2(5H)-furanone (22a, 27percent yield) and its ethyl ester (22b, 39percent yield) on heating.When the hydrolysis was carried out in 2 N NaOH at 10 deg C, 9a gave 1-(dicarboxymethyl)-2,2-dimethylcyclopropanol (23, 60percent yield) together with 22a (27percent yield).Similar hydrolysis of 9a at 30 deg C afforded 4,4-dimethyl-3-oxopentanoic acid (24, 38percent yield) and 3,3-dimethyl-2-butanone (25, 18percent yield).The bromination of 9a with Br2 caused the ring opening to give ethyl 5-bromo-4,4-dimethyl-2-(ethoxycarbonyl)-3-oxopentanoate (30) in 76percent yield.The ester 30 was cyclized to the oxetane 31 in 77percent yield.
