Catalytic Enantioselective Synthesis of Chiral Phthalides by Efficient Reductive Cyclization of 2-Acylarylcarboxylates under Aqueous Transfer Hydrogenation Conditions
作者:Bo Zhang、Ming-Hua Xu、Guo-Qiang Lin
DOI:10.1021/ol901674k
日期:2009.10.15
A new diamine ligand for asymmetrictransferhydrogenation (ATH) was discovered. The reductive cyclization of 2-acylarylcarboxylates was found to proceed highly stereoselectively by the new Ru complex-catalyzed ATH and subsequent in situ lactonization under aqueous conditions. It enables efficient access to a wide variety of 3-substituted phthalides in enantiomericallypure form.
One‐Pot Synthesis of 3‐Alkylidenephthalides from Benzoic Acids by a Rhodium‐Catalyzed
<i>ortho</i>
‐CH Acylation Process
作者:Grégory Danoun、Patrizia Mamone、Lukas J. Gooßen
DOI:10.1002/chem.201303426
日期:2013.12.16
CH functionalization: A [Rh(cod)Cl]2/CsF (cod=1,5‐cyclooctadiene) catalyst system was found to promote the straightforward synthesis of 3‐alkylidenephthalides from benzoicacids and aliphatic acids or anhydrides through a one‐pot CH acylation/acylalization/elimination cascade (see scheme).
The acid-catalysed complexation of various substituted phthalides with Cr(CO)6 has been studied. Complexation of substituted 3-benzylidene phthalides takes place at the phenyl ring in most cases, but with di-halogeno-substituted 3-benzylidene phthalides the complexation took place at the phthalide moiety. An explanation of this difference is based on molecular modelling quantum chemical calculations