A green method for the sulfination of allenic carbonyl compounds to access a wide variety of vinylic sulfones is developed. This reaction works in aqueousmedia under very mild conditions. This reaction is atom economic. A wide variety of vinylic sulfones could be obtained in moderate to excellent yields with wide functional group tolerance. The efficiency of this method is demonstrated in some reactions
Copper-Catalyzed, C–C Coupling-Based One-Pot Tandem Reactions for the Synthesis of Benzofurans Using <i>o</i>-Iodophenols, Acyl Chlorides, and Phosphorus Ylides
作者:Yunyun Liu、Hang Wang、Jie-Ping Wan
DOI:10.1021/jo5017508
日期:2014.11.7
One-pot reactions involving acyl chlorides, phosphorusylides, and o-iodophenols with copper catalysis have been established for the rapid synthesis of functionalized benzofurans. With all of these easily available and stable reactants, the construction of the target products has been accomplished via tandem transformations involving a key C–C coupling, leading to the formation of one C(sp2)–C bond
Au nanoparticlessupported on TiO2 (1 mol %) catalyze the quantitative cycloisomerization of conjugated allenones into furans under very mild conditions. The reaction rate is accelerated by adding acetic acid (1 equiv), but the acid does not participate in the protodeauration step as in the corresponding Au(III)-catalyzed transformation. The process is purely heterogeneous, allowing thus the recycling
Oxidative Cross-Coupling of Allenyl Ketones and Organoboronic Acids: Expeditious Synthesis of Highly Substituted Furans
作者:Ying Xia、Yamu Xia、Rui Ge、Zhen Liu、Qing Xiao、Yan Zhang、Jianbo Wang
DOI:10.1002/anie.201400500
日期:2014.4.7
Allenylketones are employed as coupling partners in palladium‐catalyzed oxidative cross‐coupling reactions with organoboronicacids. This reaction constitutes an efficient methodology for the synthesis of highlysubstitutedfuran derivatives. Palladium‐carbene migratory insertion is proposed as the key step in this transformation.
Generation and Rearrangement of
<i>N</i>
,
<i>O</i>
‐Dialkenylhydroxylamines for the Synthesis of 2‐Aminotetrahydrofurans
作者:Jongwoo Son、Tyler W. Reidl、Ki Hwan Kim、Donald J. Wink、Laura L. Anderson
DOI:10.1002/anie.201800908
日期:2018.5.28
provide modular access to these novel rearrangement precursors. The scope of this de novo synthesis of simple nucleoside analogues has been explored to reveal trends in diastereoselectivity and reactivity. In addition, a base‐promoted ring‐opening and Mannich reaction has been discovered to covert 2‐aminotetrahydrofurans to cyclopentyl β‐aminoacid derivatives or cyclopentenones.