disclose the first C-2-selective C–H alkenylation of quinoline N-oxides catalyzed using a heterogeneous palladium catalyst. The protocol does not require the use of an external oxidant and it is applicable to an ample substrate scope always showing excellent site selectivity. This process is made accessible by the use of a specific 1,2,3-triazolium-tagged heterogeneous polymeric catalytic system. The
Rzeszotarska,B.; Wiejak,S., Justus Liebigs Annalen der Chemie, 1968, vol. 716, p. 216 - 218
作者:Rzeszotarska,B.、Wiejak,S.
DOI:——
日期:——
Di-<i>tert</i>-butyl Dicarbonate and 4-(Dimethylamino)pyridine Revisited. Their Reactions with Amines and Alcohols<sup>1</sup>
作者:Yochai Basel、Alfred Hassner
DOI:10.1021/jo000257f
日期:2000.10.1
The reaction of BOC2O in the presence and absence of DMAP was examined with some amines, alcohols, diols, amino alcohols, and aminothiols. Often, unusual products were observed depending on the ratio of reagents, reaction time, polarity of solvent, pK(a) of alcohols, or type of amine (primary or secondary). In reactions of aliphatic alcohols with BOC2O/DMAP, we isolated for the first time carbonic-carbonic anhydride intermediates; this helps explain the formation of symmetrical carbonates in addition to the O-BOC products. In the case of secondary amines, we succeeded to isolate unstable carbamic-carbonic anhydride intermediates that in the presence of DMAP led to the final N-BOC product. The effect of N-methylimidazole in place of DMAP was also examined.
Chemoselective O-tert-butoxycarbonylation of phenols using 6,7-dimethoxyisoquinoline as a novel organocatalyst
作者:Yukako Saito、Yuichi Yoshimura、Hiroki Takahata
DOI:10.1016/j.tetlet.2010.10.114
日期:2010.12
The chemoselective O-tert-butoxycarbonylation of phenols using low levels (5-0.1 mol %) of 6,7-dimethoxyisoquinoline as a reusableorganocatalyst is described. (C) 2010 Elsevier Ltd. All rights reserved.