作者:Donald Craig、N. Paul King、Jörg T. Kley、David M. Mountford
DOI:10.1055/s-2005-918448
日期:——
pyrrol-2-ylmethyl tosylacetates undergo facile decarboxylative Claisenrearrangement upon exposure to N,O-bis(trimethylsilyl)acetamide-potassium acetate to yield the corresponding 2,3-disubstituted heteroaromatic products in good yield. However, for 1-(thien-2-yl)ethyl tosylacetates and substrates derived from 3-(hydroxyalkyl)indoles rearomatisation does not occur.
the mesopores, and serve as an efficient heterogeneous catalyst for the synthesis of heterocycle-containing diarylmethanes via Friedel-Crafts-like alkylation of (hetero)arenes by heterobenzyl acetates under mild reaction conditions without requiring any additives or an inert atmosphere. Using this strategy, the gram-scale synthesis of indole-containing diarylmethane 13 has been accomplished in good yield
2-(Chlorodiisopropylsilyl)-6-(trimethylsilyl)phenyl triflate serves as an efficient aryne precursor for intramolecular benzyne [4 + 2] or (2 + 2 + 2) cycloadditions. Key features of this precursor are (1) rapid connection of various arynophiles to the precursor via a Si–O bond and (2) generation of aryne undermildconditions using a combination of Cs2CO3 and 18-crown-6.
Gold Catalysis: Switching the Pathway of the Furan-Yne Cyclization
作者:A. Stephen K. Hashmi、Matthias Rudolph、Jürgen Huck、Wolfgang Frey、Jan W. Bats、Melissa Hamzić
DOI:10.1002/anie.200900887
日期:2009.7.27
Changing tracks: By the use of alkynyl ethers as directing elements, the furan‐yne cyclization enters a new reaction pathway. Instead of phenols, tetracycles containingtwoheteroatoms and two new stereocenters are formed (see scheme).
Palladium-catalyzed regioselective allylation of five-membered heteroarenes with allyltributylstannane
作者:Sheng Zhang、Xiaoqiang Yu、Xiujuan Feng、Yoshinori Yamamoto、Ming Bao
DOI:10.1039/c4cc10373d
日期:——
Palladium-catalyzedallylation reactions of 2-(chloromethyl)thiophenes, 2-(chloromethyl)furans, and N-protected 2-(chloromethyl)-1H-pyrroles with allyltributylstannane were described in this study. This type of allylation reaction regioselectively occurred on the heteroarene rings to produce allylated dearomatization products or allylated heteroarenes with satisfactory yields.