Green Protocol For Selective Synthesis Of N, O-heterocyclic Dirivatives

The development of green synthetic method is a hot research topic in organic chemistry.Organic synthesis in environment-friendly medium(such as water) under catalyst-free condition is an important way to achieve green synthesis.Recently the research of catalyst-free reaction in water and chemo-enzymatic system for the synthesis of bioactive compounds widened the application of green chemistry in organic synthesis.The exploration of green synthesis in new reactions and the cascade reactions attracted the research interest of chemists.Firstly we investigated the selective reactions of aminoethanol and vinyl ester of carboxylic acid(such as vinyl acrylate,divinyl succinate,divinyl adipate,divinyl sebacate,(S)-2-acetoxy-succinic acid divinyl ester) in organic solvents without catalysts. The effects of solvents and substracts were also investigated.It was found that the products of the propranolol and(S)-2-acetoxy-succinic acid divinyl ester were various in different solvents,and the six- and seven-membered heterocycles and line chain products were obtained.The structures of the products were confirmed by ¹H-NMR, ¹³C-NMR and HMBC spectra and the configurations of the products were identified by chiral HPLC with the standard sample.The mechanism for the reaction was proposed.The morpholin-2-one and morpholin-3-one were selectively synthesized in organic solvents under catalyst-free catalysts.The products of reactions of N-substituted aminoethanol and divinyl fumarate were morpholin-2-one in MTBE,while the products were morpholin-3-one in DMSO.A mechanism for the selectively reaction was proposed and some experiments demonstrated the validation of the mechanism.A new rout for the synthesis of morpholin-2-one was also investigated in water.A fast and efficient protocol which was associated with readily available starting materials,mild conditions,excellent yields,and broad range of the products in synthetic chemistry,was established for synthesis of quinoxaline,benzoxazine,and benzothiazine derivatives in water under catalyst-free conditions.The influences of the structures of amines,unsaturated carbonyl compounds and the reaction conditions on this catalyst-free reaction were systematically investigated.A new strategy for the fast synthesis heterocycles was developed and the catalytic mechanism was studied.A new method for selectively synthesis of bicyclolactones through the cascade reaction was investigated.Chemo-enzymatic method for the cascade reaction of Diels-Alder addition and transesterification reaction was used to selectively synthesize a series of optically active bicyclolactones.The influences of reaction conditions,the structure of substrates and acceptors on the cascade reaction were investigated.It was found that Trans-bicyclolactones were obtained through enzymatic transesterification/Diels-Alder addition,while the Cis-configuration compounds were afford by Diels-Alder addition/transesterification.In this thesis,90 compounds were synthesized including 7 vinyl esters,12 aminoethanol drug derivatives,11 N-aminoethanol derivatives,25 morpholinone,24 benzoheterocycles,5 1,3,8-triene derivatives,6 optically active bicyclolactones.These compounds were characterized by FTIR,¹H-NMR,¹³C-NMR and ESI-MS and 61 compounds have been confirmed to be new compounds.