Regioselective Synthesis of Bioactive Polyheterocycles: Sequential [3, 3] Sigmatropic Rearrangements of 6-(4-Aryloxybut-2-yn-1-yloxy)[1]Benzopyran-2-Ones
摘要:
7a-Methyl-13,13a-dihydro-7aH-furo[3,2-c : 5,4-f']bis-[1]benzopyran-3-ones (4a-d) are regioselectively synthesised in 65-75% yields by the sequential rearrangements of 6-(4-aryloxybut-2-yn-1-yloxy)[1]benzopyran-2-ones (3a-d) in refluxing N,N-diethylaniline (15 h). However, addition of toluene-4-sulphonic acid in the reaction mixture improved the yield (80-85%) and reduced the reaction time (10 h).
Rhodium(I)-Catalyzed Decarbonylative Spirocyclization through CC Bond Cleavage of Benzocyclobutenones: An Efficient Approach to Functionalized Spirocycles
作者:Tao Xu、Nikolas A. Savage、Guangbin Dong
DOI:10.1002/anie.201310149
日期:2014.2.10
The rhodium‐catalyzed formation of all‐carbon spirocenters involves a decarbonylative coupling of trisubstituted cyclic olefins and benzocyclobutenones through CC activation. The metal–ligand combination [Rh(CO)2Cl}2]/P(C6F5)3 catalyzed this transformation most efficiently. A range of diverse spirocycles were synthesized in good to excellent yields and many sensitive functional groups were tolerated
Selective Formation of Six-Membered Oxa- and Carbocycles by the In(III)-Activated Ring Closure of Acetylenic Substrates
作者:Wen-Wei Qiu、Karavadhi Surendra、Liang Yin、E. J. Corey
DOI:10.1021/ol202621g
日期:2011.11.4
Fifteen examples are disclosed of efficient In(III)-catalyzed six-memberedringclosure leading to bi-, tri-, and tetracyclic products.
公开了有效地In(III)催化的六元环闭合的十五个实例,其产生了双,三和四环产物。
Regioselective Synthesis of Bioactive Polyheterocycles: Sequential [3, 3] Sigmatropic Rearrangements of 6-(4-Aryloxybut-2-yn-1-yloxy)[1]Benzopyran-2-Ones
作者:K. C. Majumdar、P. Chatterjee
DOI:10.1080/00397919808004939
日期:1998.10
7a-Methyl-13,13a-dihydro-7aH-furo[3,2-c : 5,4-f']bis-[1]benzopyran-3-ones (4a-d) are regioselectively synthesised in 65-75% yields by the sequential rearrangements of 6-(4-aryloxybut-2-yn-1-yloxy)[1]benzopyran-2-ones (3a-d) in refluxing N,N-diethylaniline (15 h). However, addition of toluene-4-sulphonic acid in the reaction mixture improved the yield (80-85%) and reduced the reaction time (10 h).