33745-25-4Relevant academic research and scientific papers
Stereoselective tandem Michael-intramolecular cyclization approach to functionalized pyrroloisoindolones
Reyes, Adelfo,Regla, Ignacio,Fragoso, Mabel C.,Vallejo, Laura A.,Demare, Patricia,Jimenez-Vazquez, Hugo A.,Ramirez, Yara,Juaristi, Eusebio,Tamariz, Joaquin
, p. 11187 - 11202 (1999)
A stereoselective synthesis of pyrrolo[2,1-a]isoindol-5-ones is described. The synthesis takes place through a tandem Michael addition- intramolecular cyclization, by the base-promoted condensation of methyl N- phthaloylalaninate with conjugate acceptors at low temperature. The desired products were obtained in good yields as single isomers in only one step. Presumably, the stereoselectivity of the cyclization step is kinetically controlled by a lithium chelate species between the interacting centers. The structure of the adducts is discussed, being supported by NMR experiments and X-ray crystallography.
HYDROCARBOALKOXYLATION OF N-VINYLPHTHALIMIDE CATALYZED BY PALLADIUM COMPLEXES
Cavinato, G.,Toniolo, L.,Botteghi, C.,Gladiali, S.
, p. 93 - 100 (1982)
The hydrocarboalkoxylation of N-vinylphthalimide catalyzed by palladium tertiary phosphine complexes occurs with high selectivity towards the linear isomer when the alcohol is used also as the solvent but towards the branched isomer in the presence of an additional solvent.When triphenylphosphine is employed as the ligand, the yield and the regioselectivity towards the branched isomer increase with increasing pCO or decreasing concentration of the phosphine.Reaction in the presence of molecular hydrogen leads to higher yields, with minor changes in regioselectivity.High regioselectivities toward either the linear or the branched isomer are observed also in the presence of chiral di- or mono-phosphines, but the degree of asymmetric induction is very low.
METHOD FOR ALCOHOLYSIS OF AMIDE
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Paragraph 0041-0042; 0044-0068; 0075-0077; 0129-0135, (2020/03/01)
Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis.
An Epoxide-Mediated Deprotection Method for Acidic Amide Auxiliary
Pei, Qing-Lan,Che, Guan-Da,Zhu, Ru-Yi,He, Jian,Yu, Jin-Quan
supporting information, p. 5860 - 5863 (2017/11/10)
A practical method for the removal of a versatile acidic amide auxiliary has been developed. Facile alcoholysis of the amide in the presence of KOAc is enabled by an epoxide, which mechanistically resembles the removal of the Myers' auxiliary. The protocol has been applied to the removal of a variety of amide substrates and their C-H functionalization products with high efficiency and low cost, representing a step forward toward the development of a versatile directing group for C-H activation.
A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: Indirect use of carbon dioxide
Gehrtz,Hirschbeck,Fleischer
supporting information, p. 12574 - 12577 (2015/08/06)
Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO2 reduction product, the crystalline and air-stable N-formylsaccharin, as a CO surrogate. The carbonylation proceeds under ambient conditions in an exceptionally complementary regioselective fashion yielding the desired branched products from styrene derivatives and valuable linear esters from alkyl-substituted alkenes.
Synthesis of tetrahydrophthalazine and phthalamide (phthalimide) derivatives via palladium-catalysed carbonylation of iodoarenes
Marosv?lgyi-Haskó, Diána,Petz, Andrea,Takács, Attila,Kollár, László
experimental part, p. 9122 - 9128 (2011/12/02)
1,2,3,4-Tetrahydrophthalazin-1-one and 1,2,3,4-tetrahydrophthalazin-1,4- dione derivatives were synthesised in high (up to 85%) and low yields using 2-iodobenzyl bromide and 1,2-diiodobenzene as bifunctional substrates, respectively. Iodoarenes, carbon monoxide and various hydrazine derivatives as N-nucleophiles were used in a three-component palladium-catalysed cascade hydrazinocarbonylation. A similar palladium-catalysed reaction, the aminocarbonylation of 1,2-diiodobenzene, resulted mainly in the formation of two types of major products depending on the amine N-nucleophiles: the use of primary amines yielded N-substituted phthalimides in double carbonylation, while secondary amines react with one of the iodoarene functionalities affording the corresponding 2-iodobenzamides. Due to double carbon monoxide insertion at one or both iodoarene functionalities, ketocarboxamide-carboxamide or bis-ketocarboxamide derivatives could be isolated by the modification of the reaction conditions. Some mechanistic details of the ring-closure reactions and the conditions leading to side-products are also discussed.
Nucleophilic Substitution Reactions of (Alkoxymethylene)dimethylammonium Chloride
Barrett, Anthony G. M.,Braddock, D. Christopher,James, Rachel A.,Koike, Nobuyuki,Procopiou, Panayiotis A.
, p. 6273 - 6280 (2007/10/03)
The use of imidate esters as potential replacements for diethyl azodicarboxylate and triphenylphosphine in the Mitsunobu reaction is described. A series of secondary alcohols were allowed to react with (chloromethylene)dimethylammonium chloride, generated from dimethylformamide (DMF) and oxalyl chloride, to give imidate esters. Reaction of these salts with potassium benzoate or potassium phthalimide gave the products of SN2 substitution in excellent yields with clean inversion of stereochemistry. Optimization of reaction conditions is discussed as a means to increase the atom economy of the process by minimizing the quantity of nucleophile required.
REAGENTS AND SYNTHETIC METHODS 21. THIONYL CHLORIDE/4-(N,N-DIMETHYLAMINO)PYRIDINE COMPLEX. A SIMPLE ONE-POT METHOD FOR ESTERIFICATION OF CARBOXYLIC ACIDS.
Arrieta, A.,Garcia, T.,Palomo, C.
, p. 1139 - 1146 (2007/10/02)
Esters are obtained by a one-pot method, in which the carboxylic acid is first converted into its acyl chloride by means of thionyl chloride/4-(N,N-dimethylamino)pyridine complex as a new activating reagents.
Asymmetric Hydroformylation and Hydrocarboxylation of Enamides. Synthesis of Alanine and Proline
Becker, Y.,Eisenstadt, A.,Stille, J. K.
, p. 2145 - 2151 (2007/10/02)
Carbonyltris(triphenylphosphine)hydridorhodium (1) catalyzed the hydroformylation of N-vinylimides in the presence of optically active 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane (DIOP) or 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis(5H-dibenzophospholyl)butane (DIPHOL) to afford optically active α-amido aldehydes.Linear disubstituted N-vinylimides or -amides reacted very sluggishly, while the cyclic N-acyl-2-pyrroline (19) was very reactive.In the unsubstituted N-vinylimides moderate (20-40percent ee) asymmetric induction was observed.The optically active α-amido aldehydes were readily converted to the corresponding α-amino acids.Asymmetric hydrocarboxylation of the same substrates in the presence of bis(triphenylphosphine)palladium chloride (2) produced α-amido esters in low optical purity.
CESIUM FLUORIDE-PROMOTED SYNTHESIS OF CARBOXYLIC ACID DERIVATIVES USING 2-FLUOROPYRIDINIUM SALT
Shoda, Shin-ichiro,Mukaiyama, Teruaki
, p. 391 - 392 (2007/10/02)
In the presence of cesium fluoride, the equimolecular reactions of carboxylic acids with alcohols, amines or thiols using 2-fluoro-pyridinium salt proceeded smoothly under mild conditions to afford the corresponding carboxylic acid derivatives with base s
