New fused lactones from indolizinediones via N-acyliminium ions
摘要:
N-Arylmethylphthalimidine-3-carboxylates 3 are good precursors for the synthesis of ketones 5a,b or enols 6c-e which upon acidic treatment led to lactones 7 via an N-acyliminium ion. (C) 1998 Elsevier Science Ltd. All rights reserved.
New fused lactones from indolizinediones via N-acyliminium ions
摘要:
N-Arylmethylphthalimidine-3-carboxylates 3 are good precursors for the synthesis of ketones 5a,b or enols 6c-e which upon acidic treatment led to lactones 7 via an N-acyliminium ion. (C) 1998 Elsevier Science Ltd. All rights reserved.
Isoindolinones as Michael Donors under Phase Transfer Catalysis: Enantioselective Synthesis of Phthalimidines Containing a Tetrasubstituted Carbon Stereocenter
作者:Francesco Scorzelli、Antonia Di Mola、Laura Palombi、Antonio Massa
DOI:10.3390/molecules20058484
日期:——
Readily available chiral ammonium salts derived from cinchona alkaloids have proven to be effective phase transfer catalysts in the asymmetric Michael reaction of 3-substituted isoindolinones. This protocol provides a convenient method for the construction of valuable asymmetric 3,3-disubstituted isoindolinones in high yields and moderate to good enantioselectivity. Diastereoselectivity was also investigated
asymmetric transfer hydroxymethylation of activated isoindolinones, allowing us to prepare the enantioenriched hydroxymethylated adducts in good to excellent yields (48–96%) and enantiopurities (81:19–97:3 e.r.). To increase the reaction rate without compromising the selectivity, carefully optimized formaldehyde surrogates were employed, providing a convenient source of anhydrous formaldehyde with a base-triggered