Enantioselective Mannich Reactions with the Practical Proline Mimetic <i>N</i>-(<i>p</i>-Dodecylphenyl-sulfonyl)-2-pyrrolidinecarboxamide
作者:Hua Yang、Rich G. Carter
DOI:10.1021/jo8027938
日期:2009.3.6
highly enantioselective and diastereoselective protocol for performing Mannichreactions has been developed by using a p-dodecylphenylsulfonamide-based proline catalyst. This catalyst facilitates the use of common, nonpolar solvents and increased concentrations as compared to alternative methods. A series of syn-selective Mannichreactions is reported, including the rapid access of α- and β-amino acids surrogates
A Three-Component Ugi-Type Reaction of <i>N</i>-Carbamoyl Imines Enables a Broad Scope Primary α-Amino 1,3,4-Oxadiazole Synthesis
作者:Daniel Matheau-Raven、Elizabeth Boulter、Tatiana Rogova、Darren J. Dixon
DOI:10.1021/acs.orglett.1c02945
日期:2021.11.5
A generalsynthesis of N-protected primary α-amino 1,3,4-oxadiazoles, from N-carbamoyl imines, N-isocyaniminotriphenylphosphorane (NIITP), and carboxylic acids, is described. Featuring an isocyanide addition reaction with N-carbamoyl imines, this efficient three-component Ugi-type reaction was found to be broad in scope with respect to imine, and carboxylic acid coupling partners. Furthermore, the
A Novel Bis-Thiourea Organocatalyst for the Asymmetric Aza-Henry Reaction
作者:Constantinos Rampalakos、William D. Wulff
DOI:10.1002/adsc.200800214
日期:2008.8.4
A novelbis-thiourea BINAM-based catalyst for the asymmetricaza-Henryreaction has been developed. This catalyst promotes the reaction of N-Boc imines with nitroalkanes to afford beta-nitroamines with good yields and high enantioselectivities. This catalyst has the advantage that it can be prepared in a single step from commercially available materials. A model is proposed for the catalyst action
Highly Practical BINOL-Derived Acid-Base Combined Salt Catalysts for the Asymmetric Direct Mannich-Type Reaction
作者:Kazuaki Ishihara、Manabu Hatano
DOI:10.1055/s-0030-1258296
日期:2010.11
salt catalysts for asymmetricreactions, we developed a series of simple, practical, chiral BINOL-derived salt catalysts, such as chiral pyridinium 1,1′-binaphthyl-2,2′-disulfonates 1, chiral lithium(I) binaphtholate 2, chiral magnesium(II) binaphtholate (3), chiral calcium(II) phosphate 4, and chiral phosphoric acid 5, which were particularly effective for direct Mannich-type reactions. 1 Introduction
Synthesis of α-Amino Acid Derivatives and Peptides via Enantioselective Addition of Masked Acyl Cyanides to Imines
作者:Kin S. Yang、Viresh H. Rawal
DOI:10.1021/ja510135t
日期:2014.11.19
asymmetric synthesis of amino acid derivatives is reported. Masked acyl cyanide (MAC) reagents are shown to be effective umpolung synthons for enantioselectiveadditions to N-Boc-aldimines. The reactions are catalyzed by a modified cinchona alkaloid, which can function as a bifunctional, hydrogen bonding catalyst, and afford adducts in excellent yields (90–98%) and high enantioselectivities (up to 97