Domino Hydroarylation-Cyclization Reaction: One-Pot Synthesis of Indane-Fused 3,4-Dihydrocoumarins
作者:Jin Hyuck Joo、So Won Youn
DOI:10.1002/adsc.201200745
日期:2013.1.9
A tin(II) triflate-catalyzed dominohydroarylation–cyclizationreaction has been developed to access a wide-variety of methyleneindane-fused 3,4-hydrocoumarins. A judiciously selected bi-functional Lewis acidic catalyst has been successfully applied to promote two ring-closing events as a single-pot operation.
Photosensitised regioselective [2+2]-cycloaddition of cinnamates and related alkenes
作者:Santosh K. Pagire、Asik Hossain、Lukas Traub、Sabine Kerres、Oliver Reiser
DOI:10.1039/c7cc06710k
日期:——
An efficient method for the synthesis of substituted cyclobutanes from cinnamates, chalcones, and styrenes has been developed utilizing a visible-light triplet sensitisation mode. This reaction provides a diverse range of substituted cyclobutanes in high yields under mild conditions without the need of external additives. Good regioselectivity is obtained due to strong π–π-stacking of arene moieties
Palladium-Catalyzed Aminomethylative Oppolzer-Type Cyclization of Enynes: Access to Aminomethylated Benzofulvenes
作者:Renbin Huang、Bangkui Yu、Renren Li、Hanmin Huang
DOI:10.1021/acs.orglett.1c03720
日期:2021.12.17
A novel palladium-catalyzed Oppolzer-type cyclization reaction aided by the aminomethyl cyclopalladated complex has been developed, which provides rapid access to functionalized benzofulvenes with excellent stereoselectivity. The corresponding products can undergo Diels–Alder reaction with maleimides, providing a series of complex polycyclic compounds with excellent regio- and stereoselectivities.
Visible-Light-Promoted Generation of α-Ketoradicals from Vinyl-bromides and Molecular Oxygen: Synthesis of Indenones and Dihydroindeno[1,2-c]chromenes
作者:Santosh K. Pagire、Peter Kreitmeier、Oliver Reiser
DOI:10.1002/anie.201702953
日期:2017.8.28
can be converted by a visible‐light‐mediated photocascade reaction with molecularoxygen into either indenones or dihydroindeno[1,2‐c]chromenes. The one‐step process features key photochemical steps, that is, the initial activation of vinyl bromides through energy transfer to give α‐ketoradicals in a reaction with molecularoxygen, followed by α‐oxidation of an arene moiety by 6‐π electrocyclization
P2-Et-Mediated Deprotonation of ortho-Halobenzyl Sulfones: Synthetic Applications as Zwitterionic Synthons
作者:Ana Costa、Carmen Nájera、José M. Sansano
DOI:10.1055/s-2001-18740
日期:——
α-Sulfonyl benzylic carbanions, derived from ortho-halobenzyl sulfones 5 (Hal = Br, I), can be easily generated by the phosphazene base P2-Et and react with different electrophiles such as alkyl halides, aldehydes and ethyl acrylate. Palladium catalysed cross-coupling reactions performed at the halogen atom, followed by P2-Et-mediated alkylation-dehydrosulfinylation process using bromoacetates as electrophiles allow the preparation of ortho-substituted cinnamates.