Synthesis of (<i>Z</i>)-2-[(<i>Z</i>)-3-Alkylideneisobenzofuran-1(3<i>H</i>)-ylidene]acetic Acid Derivatives by Sequential Coupling-Cyclization between 3-(2-Iodophenyl)-3-oxopropanoic Acid Derivatives and Terminal Alkynes
3-(2-Iodophenyl)-3-oxopropanoic acid derivatives reacted efficiently with various terminal alkynes in the presence of catalytic amounts of dichlorobis(triphenylphosphine)palladium and copper(I) iodide and two molar amounts of triethylamine in N,N-dimethylformamide at room temperature to afford the corresponding (Z)-2-[(Z)-3-alkylideneisobenzofuran-1(3H)-ylidene]acetic acid derivatives in reasonable yields.
Palladium(0)-catalyzed 5- exo - dig O -cyclization/coupling of ethyl 3-(2-alkynylphenyl)-3-oxopropanoates with aryl iodides to 1,3-dihydroisobenzofurans
Palladium-catalyzed highly regioselective 5-exo-dig O-cyclization/coupling of a series of ethyl 3-(2-alkynylphenyl)-3-oxopropanoates with aryl iodides has been developed for the synthesis of (Z)-alkylidene-1,3-dihydroisobenzofuran derivatives. Reactions of ethyl 3-(2-alkynylphenyl)-3-oxopropanoates and aryl iodides are carried out in DMSO at 80 degrees C with 5 mol % Pd(PPh3)(4) and 2 equiv of Et3N as a base for 4 h in modest yields. (C) 2015 Elsevier Ltd. All rights reserved.
DBU/AgOTf Relay‐Catalysis Enabled One‐Pot Synthesis of 1,3‐Dihydroisobenzofurans and Its Conversion to Indanones
reaction of 2-alkynylbenzaldehydes and α-diazo esters for the efficient construction of 1,3-dihydroisobenzofuran derivatives has been documented. This protocol can tolerate a wide range of substrates and its scalability is demonstrated by the gram-scale reaction. Moreover, the obtained 1,3-dihydroisobenzofurans can be converted to indanone derivatives by a AgOTf-catalyzed ring recombination process. Both
DBU/AgOTf 中继催化 2-炔基苯甲醛和α-重氮酯的一锅反应用于有效构建 1,3-二氢异苯并呋喃衍生物已被记录。该协议可以容忍广泛的底物,其可扩展性由克级反应证明。此外,获得的 1,3-二氢异苯并呋喃可以通过 AgOTf 催化的环重组过程转化为茚满酮衍生物。所得产物 1,3-二氢异苯并呋喃和茚满酮都是多种药物和天然产物的重要结构单元,其结构已通过单晶 X 射线衍射分析得到明确证实。