Accessing N-Stereogenicity through a Double Aza-Michael Reaction: Mechanistic Insights
作者:Sonja Kohrt、Nico Santschi、Ján Cvengroš
DOI:10.1002/chem.201502670
日期:2016.1.4
compounds in an enantiomerically pure form. Esters of propiolic acid and chiral alcohols were evaluated as cheap and readily available Michael acceptors in a diastereoselective synthesis of N‐stereogenic compounds by means of a double aza‐Michael conjugate addition. Diastereomeric ratios of up to 74:26 and high yields were achieved with (−)‐menthyl propiolate as a substrate. Furthermore, a detailed
Synthesis and NMR study of N-heterocyclic carbenes (NHC) precursors derived from Tröger’s Base
作者:Eric MUSENGIMANA、Claver FATAKANWA
DOI:10.13005/ojc/290426
日期:2013.12.30
various catalysts have been developed but those based on Ruthenium and N-heterocyclic carbenes (NHC) ligands are particularly more efficient. Herein, we report a synthesis of NHC precursors derived from the Troger’s base and its analogues which can be used in the synthesis of the new kind of metathesis catalysts. The NHC derived from the Troger’s base present a particular chirality that could affect
A New Class of Tröger’s Base Analogues Bearing Spiro[4.5] Lactone Straps
作者:Andrew Try、Andrew Mahon、Donald Craig
DOI:10.1055/s-0028-1083341
日期:2009.2
A protocol for the introduction of spiro[4.5] lactone straps onto the Tröger’s base scaffold has been developed. The conversion was found to be most efficient when an appropriate carboxylic acid derivative reacted with 5,6,11,12-tetrahydrodibenzo[b,f][1,5]diazocines. Whilst phthaloyl dichloride was the main strap-forming precursor used, other 1,2-unsaturated dicarboxylic acids could be used in the presence of N,N′-dicyclohexylcarbodiimide.
Synthesis of Tröger’s Base Analogues via a Phase-Transfer-Catalyzed Double Aza-Michael Reaction under Base-Free Conditions
作者:Ján Cvengroš、Takuya Kamiyama、Lukas Sigrist
DOI:10.1055/s-0035-1562461
日期:——
Abstract The potential of phase-transfer catalysis in the synthesis of Tröger’s base analogues via a double aza-Michael addition has been evaluated. It has been observed that no external base is required and PTC may significantly enhance the efficiency of the process or control the selectivity. The potential of phase-transfer catalysis in the synthesis of Tröger’s base analogues via a double aza-Michael