资源描述:
《hetero diels-alder in org chem》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、HeteroDiels-AlderReactionsinOrganicChemistryLutzETietze*andGeorgKettschauInstitutfiirOrganischeChemiederGeorg-AugustUniversit/it,Tammannstr.2,D-37077G6ttingen,Germany.FAXInt.49(0)551399476TheheteroDiels-Alderreactionisoneofthemostimportantmethodsforthesynthesisofheterocy
2、cles.Inthisarticleanoverviewisgivenfortheperiodsince1989describingthereac-tionofheterobutadienessuchasoxabutadienes,thiabutadienes,azabutadienes,diaazabuta-dienes,nitroso-alkenesandnitroalkenesaswellasofheterodienophilessuchascarbonyls,thiocarbonyls,imines,iminiumsalts,a
3、zo-andnitrosocompounds.Inaddition,severalotherlesscommonheteroDiels-Alderreactionssuchascycloadditionsofthiaazabutadienes,oxa-azabutadienes,dioxabutadienes,dithiabutadienes,oxathiabutadienes,diazaoxabutadienesaswellastheuseofN-sulfinyl-phosphaalkynesandotherdienophilesar
4、ementioned.Amainpointofdiscussionisthest~reoselectivityofthereactionsandthepreparationofenantiopurecompoundseitherusingdienesanddienophilescarryingachiralauxiliaryoremployingchiralLewisacids.ApointstressedisthesynthesisofnaturalproductsusingheteroDiels-Alderreactionslead
5、ingtocarbohydrates,alkaloids,terpenes,antibiotics,mycotoxins,cyto-chalasans,antitumoragentsandseveralotherclassesofnaturalproducts.AnothertopicistheuseofhighpressureinheteroDiels-Alderreactionsdiscussingtheinfluenceontherateconstantsandthestereoselectivity.Finally,modern
6、developmentssuchasreactionsonsolidphase,theuseofcatalyticmonoclonalantibodies,transformationsinaqueoussolutionandthemicrowaveactivationaredescribed.KeywordsDiels-Alderreaction,cycloaddition,azabutadienes,oxabutadienes,diastereosel-ectivity,enantioselectivity,heterocycles
7、,naturalproducts,highpressure,Lewisacids,dihydropyrans,piperidines,carbohydrates,alkaloidsContents1IntroductionandGeneralAspects..................41.1Introduction..............................41.2StereochemicalandTheoreticalAspectsofHeteroDiels-AlderReactions............
8、........92OxaDiels-AlderReactions.......................122.1ReactionswithC-ODienophiles...............