通过苄基CH活化 将二恶英环和六氢-1 H-苯并[ f ]异色酮立体选择性合成的氧化性小二元和小二元/弗里德-克拉夫特工艺环化†
摘要:
(In)和(z)-hex-3-en-1,6-二醇和hept-3-en-1,7-二醇的1-苄醚在In( OTF)3通过顺序C-H键活化和分子内的环化的Prins,得到相应的反式-和顺-融合六氢-2- ħ -呋喃并[3,2- c ^ ]吡喃和octahydropyrano [4,3- b ]吡喃分别以良好的产率和优异的立体选择性。芳基束缚的高烯丙基苄基醚,例如(E)-和(Z)-6- arylhex -3-烯基醇经过串联普林斯/弗里德尔-克拉夫茨环化反应中的化学计量的量和DDQ的SnCl存在4经由苄基C-H键活化,以提供相应的反式-和顺式-融合六氢1 H-苯并[ f ]异色酮的收率高,具有完全的立体选择性。
Enantioselective Prins cyclization: BINOL-derived phosphoric acid and CuCl synergistic catalysis
作者:Claudia Lalli、Pierre van de Weghe
DOI:10.1039/c4cc02826k
日期:——
The first catalytic enantioselective Prins cyclization is disclosed. The reaction is catalyzed by the combination of a chiral BINOL-derived bis-phosphoric acid and CuCl. The process consists of a tandem Prins/Friedel-Crafts cyclization that affords the hexahydro-1H-benzo[f]isochromenes products with three new contiguous stereogenic centers in high yields, and good enantio- and excellent diastereoselectivities
FeCl3-catalyzed tandem Prins and Friedel–Crafts cyclization: a highly diastereoselective route to polycyclic ring structures
作者:Arun K. Ghosh、Chad Keyes、Anne M. Veitschegger
DOI:10.1016/j.tetlet.2014.05.092
日期:2014.7
Catalytic FeCl3 in the presence of 4 A molecular sieves has been shown to effect highly diastereoselective tandem Prins and Friedel-Crafts cyclization of substituted (E/Z)-6-phenylhex-3-en-1-ol and a variety of aldehydes to provide a range of polycyclic compounds in good to excellent yields. The reaction of an enantioenriched alcohol with an aldehyde provided the cyclization product without loss of optical activity. Furthermore, a Lewis acid catalyzed ring opening resulted in functionalized tetralin derivatives with multiple chiral centers. Published by Elsevier Ltd.
Oxidative Prins and Prins/Friedel–Crafts cyclizations for the stereoselective synthesis of dioxabicycles and hexahydro-1H-benzo[f]isochromenes via the benzylic C–H activation
作者:B. V. Subba Reddy、Prashant Borkar、J. S. Yadav、P. Purushotham Reddy、A. C. Kunwar、B. Sridhar、René Grée
DOI:10.1039/c1ob06489d
日期:——
stereoselectivity. Aryl tethered homoallylbenzyl ethers such as benzyl ethers of (E)- and (Z)-6-arylhex-3-enyl alcohols undergo a tandem Prins/Friedel–Crafts cyclization in the presence of stoichiometric amounts of DDQ and SnCl4via the benzylic C–H bond activation to furnish the corresponding trans- and cis-fused hexahydro-1H-benzo[f]isochromenes in good yields with complete stereoselectivity.
(In)和(z)-hex-3-en-1,6-二醇和hept-3-en-1,7-二醇的1-苄醚在In( OTF)3通过顺序C-H键活化和分子内的环化的Prins,得到相应的反式-和顺-融合六氢-2- ħ -呋喃并[3,2- c ^ ]吡喃和octahydropyrano [4,3- b ]吡喃分别以良好的产率和优异的立体选择性。芳基束缚的高烯丙基苄基醚,例如(E)-和(Z)-6- arylhex -3-烯基醇经过串联普林斯/弗里德尔-克拉夫茨环化反应中的化学计量的量和DDQ的SnCl存在4经由苄基C-H键活化,以提供相应的反式-和顺式-融合六氢1 H-苯并[ f ]异色酮的收率高,具有完全的立体选择性。