One-pot Three-component Cascade Research Articles

Three-Component One-Pot Construction of 2-Aryl-4H-benzo[4,5]thiazolo[3,2-a]pyrimidines Using Solid Calcium Carbide as a Surrogate of Gaseous Acetylene.

A concise method for the construction of 2-aryl-4H-benzo[4,5]thiazolo[3,2-a]pyrimidines using solid calcium carbide instead of gaseous acetylene as an alkyne source and 2-aminobenzothiazoles and aromatic aldehydes as substrates through one-pot three-component cascade reactions is described. The salient features for this protocol are the use of an inexpensive and easy-to-handle alkyne source, noble-metal-free condition, wide substrate scope and functional tolerance, satisfactory yield, and simple workup procedure.

One-Pot Three-Component Coupling Reaction of α-Amino Aryl Ketones, Indoles, and Perbromomethane Under Mild Conditions.

A simple and efficient one-pot three-component cascade reaction of α-amino aryl ketones, indoles, and CBr4 in moderate to good yields has been developed. This new strategy exhibits excellent mild reaction conditions and step-economy, easily accessible reactants, and simultaneous construction of three different new bonds (C=N, C–C, and N-Br) in a single step. It is worth noting that the protocol developed provides a simple and practical tool for the construction of diverse indole-containing heterocyclic frameworks, indicating its potential applications in medicinal and material chemistry.

Bmim]Br Accelerated One-Pot Three-Component Cascade Protocol for the Construction of Spirooxindole-Pyrrolidine Heterocyclic Hybrids.

Our synthetic approach for the assembly of structurally complex spirooxindole heterocyclic hybrids was based on an ionic liquid, [bmim]Br mediated one-pot three-component cascade reaction strategy involving 1,3-dipolar cycloaddition reaction of N-1-(2-pyridinylmethyl)-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones and azomethine ylide generated in situ from isatin and L-phenyl alanine, affording a series of spirooxindole–pyrrolidine heterocyclic hybrids in good-to-excellent yields. In addition to serving as the reaction medium, [bmim]Br also functioned as a catalyst in this cycloaddition reaction and hence accelerated the reaction rate affording the cycloadducts in short reaction time.

Substituent-controlled chemoselective synthesis of multi-substituted pyridones via a one-pot three-component cascade reaction.

An efficient and concise one-pot strategy for the synthesis of multisubstituted pyridones via a one-pot three-component cascade reaction catalyzed by Cs2CO3 under solvent-free conditions has been developed. The substituent-controlled chemoselective cycloaddition process involved steps including a Michael addition/ethanol elimination/intermolecular cyclization sequence utilizing anilines, diethyl acetylenedicarboxylate, and diethyl ethoxymethylenemalonate. In doing so, various 2-pyridone and 4-pyridone species (41 examples) could be obtained in good to excellent yields.

Hierarchical Beta zeolites as catalysts in a one-pot three-component cascade Prins–Friedel–Crafts reaction

Enhanced 4-aryltetrahydropyran yields are correlated with the relative concentration of medium-strength Brønsted acid sites on the mesopore surface in hierarchical zeolites.

Synthesis of 2-Amino-5-acylthiazoles by a Tertiary Amine-Promoted One-Pot Three-Component Cascade Cyclization Using Elemental Sulfur as a Sulfur Source.

A novel one-pot three-component cascade cyclization strategy for the synthesis of 2-amino-5-acylthiazoles using enaminones, cyanamide, and elemental sulfur has been developed. The reported methods have demonstrated good tolerance of various functional groups. Up to 28 2-amino-5-acylthiazole compounds bearing diverse structural differences were successfully synthesized from easily obtained starting materials with moderate to excellent yields. Our method provides an effective way for the access of valuable and potentially bioactive 2-amino-5-acylthiazole derivatives.

Thermodynamically favorable protocol for the synthesis of 2-oxazolidinones via Cu(I)-catalyzed three-component reaction of propargylic alcohols, CO2 and 2-aminoethanols

Efficient CuI/1,10-phen-catalyzed three-component cascade reaction of propargylic alcohols, CO2, and 2-aminoethanols has been firstly developed for the thermodynamically favourable preparation of 2-oxazolidinones. In the presence of commercially available CuI, 1,10-phen (1,10-phenanthroline) and t-BuOK, the cascade reaction afforded the desired products in good to excellent yields with a broad substrate scope (14 examples). The predicted copper complex Cu2I2(phen)2in situ formed from CuI and 1,10-phen could activate the triple bond through coordination. The isolation of α-alkylidene cyclic carbonate as the reaction intermediate suggests that the carboxylative cyclization of propargylic alcohol with CO2, followed by ring-opening reaction, is involved in the one-pot three-component cascade reaction.

A green one-pot three-component cascade reaction: the synthesis of 2-amino-5,8-dihydro-3H-pyrido[2,3-D]pyrimidin-4-ones in aqueous medium.

A one-pot three-component cascade reaction for the green synthesis of a new class of 2-amino-5,8-dihydro-3H-pyrido[2,3-d]pyrimidin-4-ones was developed from the condensation of aromatic aldehydes with 2,6-diaminopyrimidin-4(3H)-one and acetophenone derivatives or various cyclic ketones in the presence of a catalytic amount of sodium carbonate in a mixture of water and ethanol at 60 [Formula: see text]. This reaction led to the construction of two carbon-carbon bonds and one carbon-nitrogen bond in a single synthetic step.

One-pot three-component selective synthesis of isoindolo[2,1-a]quinazoline derivatives via a palladium-catalyzed cascade cyclocondensation/cyclocarbonylation sequence.

A practical and highly efficient procedure for the selective preparation of 6,6a-dihydroisoindolo[2,1-a]quinazoline-5,11-diones through a palladium-catalyzed one-pot three-component cascade reaction of 2-aminobenzamides with 2-bromobenzaldehydes and carbon monoxide under atmospheric pressure has been developed. This cascade reaction, in which four new C-C/C-N bonds and two new rings are simultaneously constructed, is triggered by a cyclocondensation of 2-aminobenzamides with 2-bromobenzaldehydes, followed by a Pd-catalyzed cyclocarbonylation of the in situ formed 2,3-dihydroquinazolin-4(1H)-ones with CO (1 atm). Compared with the existing methods, the present protocol has the advantages of readily available starting materials, broad substrate scope, structural diversity of products, and free of high-pressure equipment.

Thermodynamically Favorable Synthesis of 2-Oxazolidinones through Silver-Catalyzed Reaction of Propargylic Alcohols, CO2, and 2-Aminoethanols.

Development of catalytic routes to incorporate CO2 into carbonyl compounds at mild conditions remains attractive and challenging. Herein, a one-pot three-component cascade reaction of terminal propargylic alcohols, CO2 , and 2-aminoethanols through Ag(I) -based catalysis is reported for the synthesis of carbonyl compounds through C-O/C-N bond formation. This thermodynamically favorable route can be ingeniously regulated to afford a wide range of 2-oxazolidinones along with concurrent production of α-hydroxyl ketone derivatives in excellent yields and selectivity. Preliminary mechanistic studies indicate that such a process proceeds through successive formation of α-alkylidene cyclic carbonate, β-oxopropylcarbamate, and 2-oxazolidinones.

ChemInform Abstract: Synthesis of Pyrazolo[5,1‐a]isoindoles and Pyrazolo[5,1‐a]isoindole‐3‐carboxamides Through One‐Pot Cascade Reactions of 1‐(2‐Bromophenyl)buta‐2,3‐dien‐1‐ones with Isocyanide and Hydrazine or Acetohydrazide.

A novel and efficient method for the construction of the pyrazolo[5,1-a]isoindole scaffold via a one-pot three-component cascade reaction of 1-(2-bromophenyl)buta-2,3-dien-1-one with hydrazine and isocyanide promoted by a Pd catalyst is described. This cascade process proceeds through initial condensation of the allenic ketone with hydrazine followed by Pd-catalyzed isocyanide insertion into the C–Br bond and intramolecular C–N bond formation. Interestingly, when acetohydrazide was used in place of hydrazine, a more sophisticated procedure involving condensation, isocyanide insertion into C–H and C–Br bonds, deacetylation, and formation of C–C, C–O, and C–N bonds occurred to afford pyrazolo[5,1-a]isoindole-3-carboxamides with good efficiency.

Synthesis of Pyrazolo[5,1-a]isoindoles and Pyrazolo[5,1-a]isoindole-3-carboxamides through One-Pot Cascade Reactions of 1-(2-Bromophenyl)buta-2,3-dien-1-ones with Isocyanide and Hydrazine or Acetohydrazide

A novel and efficient method for the construction of the pyrazolo[5,1-a]isoindole scaffold via a one-pot three-component cascade reaction of 1-(2-bromophenyl)buta-2,3-dien-1-one with hydrazine and isocyanide promoted by a Pd catalyst is described. This cascade process proceeds through initial condensation of the allenic ketone with hydrazine followed by Pd-catalyzed isocyanide insertion into the C-Br bond and intramolecular C-N bond formation. Interestingly, when acetohydrazide was used in place of hydrazine, a more sophisticated procedure involving condensation, isocyanide insertion into C-H and C-Br bonds, deacetylation, and formation of C-C, C-O, and C-N bonds occurred to afford pyrazolo[5,1-a]isoindole-3-carboxamides with good efficiency.

Transition-metal-mediated three-component cascade cyclization: selective cage B-C(sp2) coupling of carborane with aromatics and synthesis of carborane-fused tricyclics.

Zirconium/nickel comediated one-pot three-component cascade cyclization of carboryne, alkene, and 2-bromophenyltrimethylsilylacetylene has been achieved, leading to the formation of a series of C,C,B-substituted carborane-fused tricyclics. On the basis of experimental results, a plausible mechanism is proposed including [2 + 2 + 1] cross-cyclotrimerization followed by intramolecular direct selective cage B-C(sp(2)) coupling. This represents the first example of direct cage B-C(phenyl) coupling via cage B-H activation.

One‐Pot Three‐Component Syntheses of Indoloquinolizidine Derivatives Using an Organocatalytic Michael Addition and Subsequent Pictet–Spengler Cyclization

1 pot, 2 stereocenters, 3 components, 4 bonds: An organocatalyzed one-pot three-component cascade sequence towards highly substituted indoloquinolizidines in moderate to good yields with excellent enantioselectivities was developed (see scheme). The absolute stereochemistry at C2 and C12 b was created by the organocatalyzed conjugate addition of in situ formed indole-tethered β-enaminoesters to α,β-unsaturated aldehydes, and a subsequent acid-promoted intramolecular Pictet–Spengler cyclization.

Stereoselective construction of fluorinated indanone derivatives via a triple cascade Lewis acid-catalyzed reaction

A one-pot three-component cascade reaction proceeds by way of a Lewis acid-catalyzed Knoevenagel condensation/Nazarov cyclization/electrophilic fluorination sequence to afford fluorinated 1-indanone derivatives in moderate to good yields with high diastereoselectivities.