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Recent Advances in Using Niobium Compounds as Catalysts in Organic Chemistry
(Bentham Science Publ Ltd, 2015-01-01)
Niobium is not found in nature in its free form, but usually in the form of oxides and usually with the tantalum element. The largest niobium reserves are in Brazil. The use of niobium compounds in organic synthesis has ...
Niobium Pentachloride Catalyzed Multicomponent Povarov Reaction
(Georg Thieme Verlag Kg, 2012-08-01)
A single-step method for the synthesis of furan-and pyranoquinoline derivatives through multicomponent Povarov reactions between aniline derivatives, benzaldehyde and two different enol ethers (2,3-dihydrofuran and ...
Niobium Pentachloride Catalyzed Multicomponent Povarov Reaction
(Georg Thieme Verlag Kg, 2012-08-01)
A single-step method for the synthesis of furan-and pyranoquinoline derivatives through multicomponent Povarov reactions between aniline derivatives, benzaldehyde and two different enol ethers (2,3-dihydrofuran and ...
Niobium pentachloride promoted synthesis of tetrahydropiridines by multicomponent reaction
(2013)
One-pot multicomponent synthesis of tetrahydropyridine derivatives between aniline derivatives, benzaldehyde and two different β-keto ester (methyl and ethyl acetoacetate) using niobium pentachloride as catalyst under mild ...
One-Step Synthesis of Methoxylated Phloroglucinol Derivatives Promoted by Niobium Pentachloride: An Experimental and Theoretical Approach
(2017-06-01)
Phloroglucinol derivatives are an important class of natural compounds featuring the rhodomyrtone derivatives. In this work, the synthesis of compounds with a structure core of rhodomyrtosone I is described using a ...
Facile and efficient synthesis of xanthenedione derivatives promoted by niobium pentachloride
(Springer, 2016-12-01)
Xanthenedione derivatives were synthesised in one-pot reactions between arylaldehyde derivatives and 1,3-cyclohexanedione promoted by niobium pentachloride. This new method is simple, costeffective, high-yielding with a ...
New method for the synthesis of chromeno[4,3-b]chromene derivatives via multicomponent reaction promoted by niobium pentachloride
(2017-01-01)
Chromeno[4,3-b]chromene derivatives were synthesized from multicomponent reaction between 4-hydroxycoumarin, aryl aldehyde derivatives and 1,3-cyclohexanedione promoted by niobium pentachloride. This new method is simple, ...
Efficient one-pot synthesis of 14-aryl-14H-dibenzo [a,j]xanthene derivatives promoted by niobium pentachloride
(De Gruyter Open Ltd, 2014-11-01)
A simple and efficient procedure for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives through one-pot condensation of 2-naphthol with aryl aldehydes in the presence of niobium pentachloride is described. The ...
Chemoselective condensationof beta-naphthol, dimethyl malonate, andaromatic aldehydes promoted by niobium pentachloride
(Taylor &francis Inc, 2015-01-01)
A multicomponent reaction of β-naphthol, dimethyl malonate, and aromatic aldehydes in the presence of NbCl5 as promoter is described. Under similar conditions, aromatic aldehydes with different substituents exhibited ...