scholarly journals Carbenoid-mediated nucleophilic “hydrolysis” of 2-(dichloromethylidene)-1,1,3,3-tetramethylindane with DMSO participation, affording access to one-sidedly overcrowded ketone and bromoalkene descendants§

2014 ◽  
Vol 10 ◽  
pp. 307-315 ◽  
Author(s):  
Rudolf Knorr ◽  
Thomas Menke ◽  
Johannes Freudenreich ◽  
Claudio Pires

2-(Dichloromethylidene)-1,1,3,3-tetramethylindane was “hydrolyzed” by solid KOH in DMSO as the solvent at ≥100 °C through an initial chlorine particle transfer to give a Cl,K-carbenoid. This short-lived intermediate disclosed its occurrence through a reversible proton transfer which competed with an oxygen transfer from DMSO that created dimethyl sulfide. The presumably resultant transitory ketene incorporated KOH to afford the potassium salt of 1,1,3,3-tetramethylindan-2-carboxylic acid (the product of a formal hydrolysis). The lithium salt of this key acid is able to acylate aryllithium compounds, furnishing one-sidedly overcrowded ketones along with the corresponding tertiary alcohols. The latter side-products (ca. 10%) were formed against a substantially increasing repulsive resistance, as testified through the diminished rotational mobility of their aryl groups. As a less troublesome further side-product, the dianion of the above key acid was recognized through carboxylation which afforded 1,1,3,3-tetramethylindan-2,2-dicarboxylic acid. Brominative deoxygenation of the ketones furnished two one-sidedly overcrowded bromoalkenes. Some presently relevant properties of the above Cl,K-carbenoid are provided in Supporting Information File 1.

1994 ◽  
Vol 59 (5) ◽  
pp. 1126-1136 ◽  
Author(s):  
Vladimír Valenta ◽  
Jiří Urban ◽  
Jan Taimr ◽  
Zdeněk Polívka

4-(Aminomethyl)-1-benzyl-2-oxopyrrolidine (VI) was transformed by treatment with (4-benzhydrylpiperazin-1-yl)carbonyl chlorides IIIb - IIId and with (4-methylpiperazin-1-yl)carbonyl chloride (IIIa) to the carboxamides IVa - IVd. Heating of 1-(ethoxycarbonylmethyl)-2,4-dioxopyrrolidine (XIX) in acetonitrile in the presence of water afforded XVIIIa. Treatment with ammonia led to the diamide XVIIIc, while alkaline hydrolysis of XVIIIa gave the dicarboxylic acid XVIIIb. 4-(Aminomethyl)-1-(4-methylthiobenzyl)-2-oxopyrrolidine (XII) was prepared by the reaction of 4-(methylthio)benzylamine with itaconic acid and the following sequence of reactions starting from the obtained carboxylic acid VII including esterification, reduction and treatment the obtained alcohol IX with thionyl chloride, synthesis of phthalimido derivative XI and hydrazinolysis. Amine XII added to 4-chlorophenyl isocyanate formed XIII. The compounds prepared were tested for nootropic activity.


1999 ◽  
Vol 64 (2) ◽  
pp. 389-407 ◽  
Author(s):  
Pavel Pihera ◽  
Hana Dvořáková ◽  
Jiří Svoboda

2-Vinyl- (2) and 3-vinyl[1]benzothieno[3,2-b]furan (3) react with dimethyl acetylenedicarboxylate, methyl propiolate, maleic anhydride, or acrylonitrile endo-selectively as dienes to afford new [1]benzothieno[3,2-b][1]benzofuran derivatives 7-20. cis-Anhydrides 13 and 18 were transformed into dimethyl esters 21 and 22, respectively. It was shown that the base-catalyzed hydrolysis of 13 and 18 is accompanied by rearrangement of double bond in 13 and cis/trans isomerization of carboxylic group. Diesters 21 and 22, and nitriles 20 and 24 were aromatized by treatment with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Selective monodecarboxylation of [1]benzothieno[3,2-b][1]benzofuran-8,9-dicarboxylic acid (26) and [1]benzothieno[3,2-b][1]benzofuran-6,7-dicarboxylic acid (27) afforded [1]benzothieno[3,2-b][1]benzofuran-8-carboxylic acid (28) and [1]benzothieno[3,2-b][1]benzofuran-7-carboxylic acid (29), respectively.


Author(s):  
Carla S. Valdivieso Ramirez ◽  
Feral Temelli ◽  
Marleny D.A. Saldaña

1999 ◽  
Vol 23 (3) ◽  
pp. 174-175
Author(s):  
E. Abdel-Ghani

The orientation of cyclization of the reaction of methyl aroylacrylate (1) and aroylacrylic acid (8) with ethyl acetoacetate and/or thiourea leading to the formation of 4-aroylmethylcyclopentane-1,3-dione (2) 5-aryl-3-oxocyclohexene-1,2-dicarboxylic acid (9), 2-imino-5-aroylmethylthiazolidin-4-one (11) and 6-aryl-2-sulfonylpyrimidine-4-carboxylic acid (14) depends on the medium employed; some compounds show moderate antiviral activities against tobacco necrosis virus.


Author(s):  
Carla S. Valdivieso Ramirez ◽  
Jose E. Sanchez Gallego ◽  
Michael Gänzle ◽  
Feral Temelli ◽  
Marleny D.A. Saldaña

1992 ◽  
Vol 70 (5) ◽  
pp. 1492-1505 ◽  
Author(s):  
Peter Yates ◽  
Magdy Kaldas

Treatment of 2-norobornene-1-carboxylic acid (7) with one equivalent of methyllithium in ether followed by a second molar equivalent after dilution with tetrahydrofuran gave 1-(norborn-2-en-lyl)ethanone (10) and only a trace of the tertiary alcohol 11. Reaction of 7 with formic acid followed by hydrolysis gave a 4:3 mixture of exo-3- and exo-2-hydroxynorbornane-1-carboxylic acid (16 and 17), whereas oxymercuration–demercuration gave only the exo-3-hydroxy isomer 16. Oxidation of 16 and 17 gave 3- and 2-oxonorbornane-1-carboxylic acid (27 and 29), respectively. Oxymercuration–demercuration of 10 gave exclusively 1-(exo-3-hydroxynorborn-1-yl)ethanone (30), which was also prepared by treatment of 16 with methyllithium in analogous fashion to that used for the conversion of 7 to 10. Oxidation of 30 gave 1-(3-oxonorborn-1-yl)ethanone (1). Dehydrobromination of exo-2-bromonorbornane-1-acetic acid and dehydration of 2-hydroxy-norbornane-2-acetic acid derivatives gave 1-(norborn-2-ylidene) acetic acid derivatives to the exclusion of norborn-2-ene-1 -acetic acid derivatives. Treatment of exo-5-acetyloxy-2-norobornanone (52) with ethyl bromoacetate and zinc gave ethyl exo-5-acetyloxy-2-hydroxynorbornane-(exo- and endo-2-acetate (53 and 54). Reaction of 53 with hydrogen bromide gave initially ethyl endo-3-acetyloxy-exo-6-bromonorbornane-1-acetate (59), which was subsequently converted to a mixture of 59 and its exo-3-acetyloxy epimer 61. Catalytic hydrogenation of this mixture gave a mixture of ethyl endo- and exo-3-acetyloxynorbornane-1 -acetate (62 and 63). Basic hydrolysis of this gave a mixture of the corresponding hydroxy acids, 70 and 71; the former was slowly converted to the latter at pH 5. Oxidation of the mixture of 70 and 71 gave 3-oxonorbornane-1-acetic acid (72). Treatment of the mixture with methyllithium as for 16 gave a mixture of 1-(endo- and exo-3-hydroxynorborn-1-yl)-2-propanone (73 and 74), which was oxidized to 1-(3-oxo-norborn-1-yl)-2-propanone (2). Reaction of exo-2-hydroxynorbornane-1-acetic acid lactone (75) with methyllithium in ether gave (1-(exo-2-hydroxynorborn-1-yl)-2-propanone (76), which on oxidation gave the 2-oxo isomer 78 of 2.


1984 ◽  
Vol 62 (9) ◽  
pp. 1840-1844 ◽  
Author(s):  
Karl R. Kopecky ◽  
Alan J. Miller

Treatment of methyl hydrogen decahydro-1,4:5,8-exo,endo-dimethanonaphthalene-4a,8a-dicarboxylate with lead tetraacetate in benzene – acetic acid replaces the carboxyl group by an acetoxy group. Hydrolysis of this product with 25% sulfuric acid at 130 °C forms 8a-hydroxydecahydro-1,4:5,8-exo,endo-dimethanonaphthalene-4a-carboxylic acid 10. The reaction between 10 and benzenesulfonyl chloride in pyridine containing triethylamine at 95 °C produces anti-sesquinorbornene 1 in 34% yield. In the absence of triethylamine 1 is converted to the hydrochloride. The iodohydroperoxide of 1 is converted by silver acetate at 0 °C to the diketone in a luminescent reaction. The 1,2-dioxetane could not be isolated. Decahydro-1,4:5,8-exo,exo-dimethanonaphthalene-4a,8a-dicarboxylic anhydride is converted slowly by methoxide ion in methanol at 150 °C to the monomethyl ester which then undergoes demethylation. The isomeric exo,endo anhydride undergoes reaction readily with methoxide ion at 80 °C.


2021 ◽  
Vol 08 ◽  
Author(s):  
Harshica Fernando ◽  
Ananda S. Amarasekara

Background: Polycarboxylic acids are of interest as simple mimics for cellulase enzyme catalyzed depolymerization of cellulose. In this study, DFT calculations were used to investigate the effect of structure on dicarboxylic acid organo-catalyzed hydrolysis of cellulose model compound D-cellobiose to D-glucose. Methods: Binding energy of the complex formed between D-cellobiose and acid (Ebind), as well as glycosidic oxygen to dicarboxylic acid closest acidic H distance were studied as key parameters affecting the turn over frequency of hydrolysis in water. Result: α-D-cellobiose - dicarboxylic acid catalyst down face approach showed high Ebind values for five of the six acids studied; indicating the favorability of down face approach. Maleic, cis-1,2-cyclohexane dicarboxylic, and phthalic acids with the highest catalytic activities showed glycosidic oxygen to dicarboxylic acid acidic H distances 3.5-3.6 Å in the preferred configuration. Conclusion: The high catalytic activities of these acids may be due to the rigid structure, where acid groups are held in a fixed geometry.


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