Efficient and Expeditious Synthesis of Di- and Trisubstituted Thiazoles in PEG Under Catalyst-Free Conditions

An efficient and expeditious catalyst-free protocol was developed for the construction of di- and trisubstituted thiazoles from α-haloketones and thioureas/thioamides in PEG. The reaction was carried out at ambient temperature, and the products were obtained in excellent isolated yields (91–98%). Additionally, PEG could be recovered easily and was reused without evident loss in activity.     

Amberlite IRA-400 (OH−) as a Catalyst in the Preparation of 4H-Benzo[b]pyrans in Aqueous Media

A quaternary ammonium hydroxide–type of anion exchange resin (Amberlite IRA-400) was found to be an effective and reusable catalyst for the synthesis of various 4H-benzo[b]pyran derivatives via a one-pot, three-component condensation in aqueous media. Short reaction time, easy and quick isolation of the products, environmentally friendly procedure, excellent chemoselectivity, and excellent yields are the main advantages of this procedure.     

Efficient Deallylation of Allyl Phenyl Ethers by Molecular Iodine in PEG-400 and Their Utility for Flavone Synthesis

Rapid and efficient deallylation of allyl phenyl ethers by molecular iodine (20 mol%) in polyethylene glycol-400 at 60 °C has been reported. This method has short reaction time, readily available catalyst, and reuse of reaction medium with good yield. The utility of this methodology has been extended to flavone synthesis.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Multicomponent reactions in PEG-400: ruthenium-catalyzed synthesis of substituted pyrroles

An efficient and eco-friendly method for the synthesis of substituted pyrroles has been developed via ruthenium-catalyzed multicomponent reaction of ketone, amine, and ethylene glycol in PEG-400 as solvent medium without using any external ligand. The catalytic system and solvent can be recycled with the same, as well as different, ketones with minimum loss of Ru-catalyst activity.     

Practical Preparation of Esters and Thioacetates from Alkyl Halides and Carboxylates or Thioacetate Catalyzed by PEG400 without Solvent

Carboxylic esters and thioacetates were conveniently prepared in good to excellent yields under mild conditions by the reaction of alkyl halides with sodium carboxylates or sodium thioacetate catalyzed by PEG400 in the absence of solvents.     

A remarkably simple N-formylation of anilines using polyethylene glycol

N-Formylation of anilines has efficiently been carried out at room temperature in excellent yields by treatment with formic acid in polyethylene glycol (PEG-400). No additional solvent and catalyst are required.     

镧对SS400钢组织及力学性能的影响

研究了镧对SS400钢常温及低温力学性能的影响。结果表明,SS400钢的强度、塑性、冲击韧性以及硬度随镧含量的增加能够得到明显改善,但当镧加入量过大时,会造成SS400钢的强度、塑性、冲击韧性下降。将镧含量控制在0.016%左右能够有效提高其各项力学性能。镧提高SS400钢的力学性能,是其对钢净化钢液、变质夹杂、微合金化综合作用的结果。     

PEG-400 as an efficient and recyclable reaction medium for the synthesis of 2-aryl-2-methyl-4,5-diphenyl-2,3- dihydro-2H-imidazoles

A productive natural method has been produced for the synthesis of 2-aryl-2-methyl-4,5-diphenyl-2,3-dihydro-2H-imidazoles in great yields under catalyst free-conditions utilizing polyethylene glycol (PEG-400) as a green reaction medium. The highlights of this new method are shorter reaction times, good yields, room temperature, and use of nontoxic, inexpensive, and recyclable PEG-400.     

La(OTf)3-catalyzed,three-component synthesis of spiro[Indolo-3,10′-indeno[1,2-b]quinolin]-2,4,11′-triones in PEG-400 under conventional heating and ultrasonic irradiation

An efficient La(OTf)₃-catalyzed three-component reaction has been developed for the synthesis of highly substituted spiro[indolo-3,10′-indeno[1,2-b]quinolin]-2,4,11′-triones in polyethylene glycol (PEG-400) under conventional heating and ultrasonic irradiation. The most exciting feature of this methodology is its mechanism involving the unusual ring opening of an isatin moiety followed by recyclization. All the reactions resulted in good yield of products. The important features of this reaction are use of green solvent, good yields, less reaction times, and recyclability of the catalyst.     

Efficient and green microwave-assisted one-pot synthesis of azaindolizines in PEG-400 and water

A facile, convenient, environmentally benign, and one-pot synthesis of imidazo[1,2-a]pyridines from 2-aminopyridines and in-situ generated phenacyl bromides under microwave irradiation in polyethylene glycol (PEG-400) and water (1:2) has been developed. The protocol provides a better alternative to the existing method as it involves utilization of in-situ-generated α-bromoacetophenones, avoids the use of lachrymatric α-haloketones as well as volatile toxic organic solvents, and reduces the reaction time to obtain excellent yield.