Microwave‐Assisted Aqueous Reactions: An Efficient Route to Benzodiazepines

Abstract

Microwave‐assisted three‐Select for access options to this article (DOI: 10.1039/b913846c) reaction has been established for the synthesis of benzodiazepines. This reaction promoted by HOAc was conducted by using readily available and inexpensive starting materials in water under microwave irradiation. The present green synthesis shows fascinating characteristics such as the use of water as the reaction solution, concise one‐pot conditions, short reaction periods, easy purification, and reduced waste production without the use of any strong acids or metal promoters.

Immobilized nickel boride nanoparticles on magnetic functionalized multi-walled carbon nanotubes: a new nanocomposite for the efficient one-pot synthesis of 1,4-benzodiazepines

“…In recent years, extensive investigations have been devoted to exploring the applicability of one-pot multicomponent reactions (MCRs) in the development of facile, straightforward, and highly efficient methodologies for the synthesis of a broad range of 1,4-benzodiazepines. 18 Among them, a number of catalytic systems and methodologies for the synthesis of 1,4-benzodiazepines based on the condensation of o -phenylenediamine with dimedone and various aldehydes, each of which holds a unique position in the synthesis of heterocyclic compounds, have been reported by researchers, such as UiO-66 MOF, 31 La 2 O 3 /La(OH) 3 , 33 GO nanosheets, 34 Gr@TiO 2 NCs, 35 Cu( ii )/PI-COF, 36 acetic acid/water under microwave irradiation, 37 sulfated polyborate, 38 B(HSO 4 ) 3 , 39 l -proline, 40 CuFe 2 O 4 , 41 Fe(OTs) 3 /SiO 2 , 42 CoFe 2 O 4 @GO-K22, 43 CoFe 2 O 4 @SiO 2 @NH-NH 2 -PCuW, 44 CeO 2 /CuO@GQDs@NH 2 , 45 [H-PFBA][PF 6 ], 46 [H-NMP][HSO 4 ], 47 ZnS nanoparticles, 48 Fe 3 O 4 @chitosan, 49 Fe( iii )-NicTC@nSiO 2 , 50 SrFe 12 O 19 , 51 chitosan functionalized by triacid imide, 52 HBF 4 –SiO 2 , 53 SPINOL-derived chiral phosphoric acid, 54 and oxalic acid. 55 Although each of these methods has its own advantages, they also have several shortcomings that need to be addressed.…”

Ferrocene anchored activated carbon as a versatile catalyst for the synthesis of 1,5-benzodiazepines via one-pot environmentally benign conditions

“…18,19 Therefore, numerous acidic reagents such as boron triuoride etherate, polyphosphoric acid, ytterbium(III) triate, gallium(III) triate, lead nitrate, acetic acid under microwave conditions and ionic liquids have also been used for the synthesis of benzodiazepines. [21][22][23][24][25][26] However, almost all the reagents suffer major drawbacks such as high cost, high acidity and less eco-friendly. To over these drawbacks, in recent years researchers have started exploring activity of different solid acid catalysts such as sulfated zirconia, Al 2 O 3 /P 2 O 5 , Ag 3 PW 12 O 40 , PVP-FeCl 3 , and zeolite catalysts towards synthesis of benzodiazepines by condensation of o-phenylenediamine (OPDA) with different carbonyl compounds.…”

Organocatalytic Green Approach Towards the Fabrication of Fused Benzo N,N‐containing Heterocycles Facilitated by Ultrasonic Irradiation

“…The synthesis of these heterocycles has been achieved by employing a wide range of catalysts, which include salts , acids , ionic liquids , and nano‐catalysts . The great demand for syntheses involving environmental benign protocol has prompted the replacement of expensive and hazardous catalysts with inexpensive and nontoxic ones.…”