Gold-Catalyzed Formal Cycloaddition of 2-Ethynylbenzyl Ethers with Organic Oxides and α-Diazoesters
作者:Samir Kundlik Pawar、Chiou-Dong Wang、Sabyasachi Bhunia、Appaso Mahadev Jadhav、Rai-Shung Liu
DOI:10.1002/anie.201303016
日期:2013.7.15
A world of possibilities: Gold‐catalyzed reactions of 2‐ethynylbenzyl ethers with organicoxides and α‐diazoesters gave 1,3‐dihydroisobenzofuran and naphthalene derivatives, respectively (see scheme; EWG=electron‐withdrawing group). Mechanisms for the formation of the formal cycloadducts were elucidated by isotope labeling.
Gold(I)-Catalyzed Enantioselective Carboalkoxylation of Alkynes
作者:Weiwei Zi、F. Dean Toste
DOI:10.1021/ja407150h
日期:2013.8.28
A highly enantioselective carboalkoxylation of alkynes catalyzed by cationic (DTBM-MeO-Biphep)gold(I) complexes is reported. Various optically active β-alkoxyindanone derivatives were obtained in good yields with high enantioselectivities. Furthermore, this methodology was extended to the enantioselective synthesis of 3-methoxycyclopentenones. The reaction is proposed to proceed through an enantioselective
The syntheses of 2,2′-spirobi[indene] derivatives based on a gold(I)-catalyzed tandem strategy involving intramolecular methoxylation/double aldol condensation were achieved. Examination of the scope of this tandem reaction by using a batch of alkynone substrates disclosed that the reaction possessed a good functional group tolerance. A cationic gold(I) catalyst/protonic acid-catalyzed mechanism for
Cu-Catalyzed 1,2-Dihydroisoquinolines Synthesis from <i>o</i>-Ethynyl Benzacetals and Sulfonyl Azides
作者:Lang Sun、Yuanxun Zhu、Ping Lu、Yanguang Wang
DOI:10.1021/ol402996x
日期:2013.11.15
An efficient synthesis of 1,3-/1,1-dialkoxy 1,2-dihydroisoquinolines from o-ethynylbenzacetals and sulfonyl azides via a cascade process combining copper-catalyzed alkyne azide cycloaddition (CuAAC), Dimroth rearrangement, 1,5-OR shift/1,5-H shift, and 6 pi-electrocyclic ring closure (6 pi-ERC) is described. Extension of the produced 1,3-dialkoxy-1,2-dihydroisoquinolines to isoquinolium salts is also disclosed.