Remarkably Slow Rotation about a Single Bond between an sp<sup>3</sup>-Hybridised Carbon Atom and an Aromatic Ring without<i>ortho</i>Substituents
作者:Sarah Murrison、David Glowacki、Christian Einzinger、James Titchmarsh、Stephen Bartlett、Ben McKeever-Abbas、Stuart Warriner、Adam Nelson
DOI:10.1002/chem.200802127
日期:2009.2.16
ortho substituents! A series of polycycles were prepared by using a three‐component Joullié–Ugi reaction. The rate of rotationabout the bond between a highly hindered bridgehead and a phenyl ring with no ortho substituents was measured, and was highly dependent on the substitution. Rotamer half‐lives of up to 21 h at 298 K were observed (see figure). Rotamers resulting from this restricted rotation
[reaction: see text] Palladium-catalyzedcross-coupling of vinyl- and arylstannanes with pi-electron-deficient heteroaromatics was performed in good yields. This Stille-type reaction was carried out with a methylthioether function as an electrophile in the presence of a copper(I) bromide-dimethyl sulfide complex.
The palladium-catalyzed coupling reaction of 3-thiomethyl-1,2,4-triazine 1 with different organoboron compounds in the presence of copper(I) 3-methylsalicylate proceeds to afford the corresponding 3-substituted-1,2,4-triazines in good yield. This approach leads very easily to a large range of C-5 and C-6 unsubstituted as-triazines.
Synthesis of Skeletally Diverse Alkaloid-Like Small Molecules
作者:Sarah Murrison、Sushil K. Maurya、Christian Einzinger、Ben McKeever-Abbas、Stuart Warriner、Adam Nelson
DOI:10.1002/ejoc.201100116
日期:2011.4
synthetic approach to skeletallydiversealkaloid-like compounds, involving two consecutive three-component reactions, was developed. First, reaction between a range of secondary amines, carbonyl compounds and triazines yielded cyclic imines. Crucially, the identity of the substituents in the amine and carbonyl compound components determined ― through a "folding" pathway - the alkaloid-like scaffold that was