Formation of Optically Pure Cyclic Amines by Intramolecular Conjugate Displacement
摘要:
Intramolecular conjugate displacement (ICD) has been applied to the Morita-Baylis-Hillman adducts formed from (5S)-5-(l-menthyloxy)-2(5H)-furanone and aldehydes that carry a protected beta- or gamma-amino group. DIBAL-H reduction of the resulting ICD products releases optically pure six- or seven-membered cyclic amines having a stereogenic center a to nitrogen.
Synthesis of Dibenzoheteropines of Group 13–16 Elements via Ring-Closing Metathesis
作者:Takanori Matsuda、Shinya Sato
DOI:10.1021/jo4001993
日期:2013.4.5
The ring-closingmetathesis (RCM) of bis(2-vinylphenyl)silanes in the presence of the second-generation Hoveyda–Grubbs catalyst in toluene at 100 °C afforded dibenzo[b,f]silepines in excellent yields. Other dibenzoheteropines of group 13–16 elements were also prepared via the RCM of the corresponding heteroatom-tethered dienes.
alkylthiolation of alkenes, initiated by dimethyl(methylthio)sulfonium salts and the subsequent addition of various heteronucleophilies has been well-established. Regarding the use of carbon nucleophiles, however, only carefully designed sp-type carbon sources have been successfully applied. We herein present our findings on the methylthiolation of alkenes with dimethyl(methylthio)sulfonium trifluoromethanesulfonate
Microwave-Enhanced Carbonylative Generation of Indanones and 3-Acylaminoindanones
作者:Xiongyu Wu、Peter Nilsson、Mats Larhed
DOI:10.1021/jo048375g
日期:2005.1.1
incomplete conversions of sluggish o-styryl bromides and chlorides were realized. Internal and chemoselective palladium(0)-catalyzed Heck arylations of enamides afforded suitable starting materials for subsequent rapid ring-closing reactions. Microwave-heated intramolecular in situ carbonylation of these electron-rich and sterically congested olefins conveniently afforded eight functionalized 3-acylaminoindanone
A Visible-Light-Mediated Oxidative CN Bond Formation/Aromatization Cascade: Photocatalytic Preparation of N-Arylindoles
作者:Soumitra Maity、Nan Zheng
DOI:10.1002/anie.201205137
日期:2012.9.17
Just add light and air: Structurally diverse N‐arylindoles can be prepared from readily prepared o‐styryl anilines through visible‐light photocatalysis. The reaction, which is conducted open to air, is mediated by [Ru(bpz)3](PF6)2 (bpz=2,2′‐bipyrazine) and involves both CNbondformation and aromatization (see scheme). Using suitably substituted substrates, a 1,2‐carbon shift can be also incorporated
只需添加光和空气:可以通过可见光光催化从容易制备的邻苯乙烯基苯胺制备结构多样的N-芳基吲哚。该反应在空气中进行,由 [Ru(bpz) 3 ](PF 6 ) 2 (bpz=2,2′-联吡嗪)介导,涉及 C N 键形成和芳构化(见方案)。使用适当取代的底物,1,2-碳转移也可以纳入该级联反应中。
Rh-Catalyzed [4 + 2] Carbocyclization of Vinylarylaldehydes with Alkenes and Alkynes Leading to Substituted Tetralones and 1-Naphthols
Regio-, diastereo-, and enantioselectiveintermolecular [4 + 2] carbocyclizations of vinylarylaldehydes with alkenes and alkynes leading to substituted tetralones and 1-naphthols have been developed by using a cationic rhodium(I)/dppb or dppp complex as a catalyst.