Palladium-Catalyzed Direct C−H Arylation of <i>N</i>-Iminopyridinium Ylides: Application to the Synthesis of (±)-Anabasine
作者:Alexandre Larivée、James J. Mousseau、André B. Charette
DOI:10.1021/ja710073n
日期:2008.1.1
Palladium-catalyzed direct C-H arylation of N-iminopyridinium ylides provides a powerful and versatile method for the synthesis of functionalized piperidines in good yields. Chemoselective functionalization of the pyridinium ring in the presence of a pyridine substituent is possible as exemplified by the expedient synthesis of anabasine in 61% overall yield over three steps.
Copper-Catalyzed Direct Ortho-Alkylation of <i>N</i>-Iminopyridinium Ylides with <i>N</i>-Tosylhydrazones
作者:Qing Xiao、Lin Ling、Fei Ye、Renchang Tan、Leiming Tian、Yan Zhang、Yuxue Li、Jianbo Wang
DOI:10.1021/jo4002883
日期:2013.4.19
Copper-catalyzedcross-coupling of N-tosylhydrazones with N-iminopyridinium ylides leads to the direct C–H alkylation. This direct C–H bond alkylation transformation uses inexpensive CuI as the catalyst without any ligand. The reaction is operationally simple and conducted under mild conditions, giving the corresponding alkylated pyridines in moderate to good yields. DFT calculation provides insights
Alkynyl Thioethers in Gold-Catalyzed Annulations To Form Oxazoles
作者:Raju Jannapu Reddy、Matthew P. Ball-Jones、Paul W. Davies
DOI:10.1002/anie.201706850
日期:2017.10.16
regioselective, and convergent access to densely functionalized oxazoles is realized in a functional-group tolerant manner using alkynylthioethers. Sulfur-terminated alkynes provide access to reactivity previously requiring strong donor-substituted alkynes such as ynamides. Sulfur does not act in an analogous donor fashion in this gold-catalyzed reaction, thus leading to complementary regioselective outcomes
The gold–acid‐co‐catalyzed synthesis of nine series of fused azaheterocycles with structural diversity starting from the same synthons as readily available propargylic hydroperoxides and aromatic amines has been achieved. The overall tandem process consists in a gold‐catalyzed hydroperoxide rearrangement/Michaelreaction followed by a final acid‐catalyzed cyclization.
Benzoyl Peroxide Promoted Radical<i>ortho</i>-Alkylation of Nitrogen Heteroaromatics with Simple Alkanes and Alcohols
作者:Lei Fang、Liangshun Chen、Jianjun Yu、Limin Wang
DOI:10.1002/ejoc.201403479
日期:2015.3
A catalytic amount of benzoylperoxide (BPO)-initiated cross-dehydrogenative coupling reaction of N-iminopyridine ylides with simplealkanes and alcohols leads to the corresponding 2-alkylpyridines with high regioselectivity in moderate to good yields without an additional reduction step to remove the activated group.