6237-59-8Relevant articles and documents
Pd(0)-catalyzed selective [2 + 2 + 2] cycloaddition of dimethyl nona- 2,7-diyne-1,9-dioate derivatives with dimethyl acetylenedicarboxylate
Yamamoto, Yoshihiko,Nagata, Asako,Itoh, Kenji
, p. 5035 - 5038 (1999)
In the presence of 2.5 mol % of Pd2(dba)3 and 5 mol % of PPh3, nearly equimolar mounts of dimethyl nona-2,7-diyne-1,9-dioate derivatives and dimethyl acetylenedicarboxylate (DMAD) were reacted in toluene at 110 °C to give
Palladium-Catalyzed [3+2] and [2+2+2] Annulations of 4-Iodo-2-quinolones with Activated Alkynes through Selective C?H Activation
Yamamoto, Yoshihiko,Jiang, Jiyue,Yasui, Takeshi
, p. 3749 - 3757 (2020)
The palladium-catalyzed reaction of 4-iodo-2-quinolones with activated alkynes was investigated. Cyclopenta[de]quinoline-2(1 H)-ones and/or phenanthridine-6(5 H)-ones were obtained through [3+2] annulation involving aromatic C?H activation or [2+2+2] annulation involving vinylic C?H activation, respectively. Reasonable mechanisms for the formation of these annulation products have been proposed based on density functional theory calculations.
Unexpected formation and conversion: Role of substituents of 1,3-ynones in the reactivity and product distribution during their reactions with Ru3(CO)12
Xu, Lei,Jiang, Liping,Li, Shasha,Zhang, Guofang,Zhang, Weiqiang,Gao, Ziwei
, p. 1478 - 1486 (2019)
The reactions of Ru3(CO)12 with alkynyl ketones R1CCC(O)R2 (R1 = Et, R2 = Me (1); R1 = Ph, R2 = Me (2); R1 = n-hexyl, R2 = Ph (3); R1 = H, R2 = CH3 (4); and R1 = C(O)OCH3, R2 = OCH3 (5)) proceeds in toluene with the formation of three ruthenoles (1a-3a), four CO-inserted binuclear clusters (1b-2b, 1c and 3c), a tetranuclear cluster 4a, a binuclear cluster 5a and a cyclotrimerization product 5b. Clusters 1a-3a, 1b, 2b, 1c and 3c were isolated from the reactions of Ru3(CO)12 with two equivalents of the corresponding ketones 1-3; 4a and 5a were collected by adding 4 and 5 to Ru3(CO)12 in molar ratios of 1:1 and 1:3, respectively; 5b was obtained by adding 5 to 5a in a molar ratio of 2:1. All compounds were characterized by NMR, FT-IR, and MS-ESI, and most of them were structurally verified by single crystal X-ray diffraction. Although the reaction products of 1-3 and Ru3(CO)12 exhibit similar cluster frameworks of usual ruthenoles and CO-inserted binuclear clusters, the isolation of the clusters 1b-2b, 1c and 3c reveals their strong dependence on both electronic and steric effects of the substituents of the 1,3-ynones 1-3. In addition, detailed investigations suggested that the high reactivity of the terminal hydrogen atom and electron-withdrawing property of the carbonyl group in 4 play a key role in the formation of 4a, and that the structurally unusual 5a is an intermediate in the formation of 5b.
Catalytic three-component synthesis of conjugated dienes from alkynes via Pd0, Pd(II), and Pd(IV) intermediates containing 1,2-diimine
Van Belzen,Hoffmann,Elsevier
, p. 1743 - 1745 (1997)
Direct, efficient, selective, and catalytic all describe the synthesis of conjugated dienes from two molecules of alkyne, an organic halide, and tetramethyltin with 1 mol% of a (1,2-diimine)palladium complex in DMF (see the catalytic cycle involving Pd0. Pd(II) and Pd(IV) species on the right) Palladium-phosphane complexes do not catalyze this reaction. Furthermore, 1,4-dihalo-l,3-dienes were synthesized stoichiometrically from alkynes and molecular halogen.
Rhodium-catalyzed linear cross-trimerization of two different alkynes with an alkene and two different alkenes with an alkyne
Kobayashi, Masayuki,Tanaka, Ken
, p. 9225 - 9229 (2012)
Crossing paths with rhodium: A cationic RhI/H8-BINAP complex has been found to catalyze the linear cross-trimerization of terminal alkynes, acetylenedicarboxylates, and acrylamides to give substituted trienes. The asymmetric linear c
A Rh(I)-Catalyzed Cascade Cyclization of 1,5-Bisallenes and Alkynes for the Formation of cis-3,4-Arylvinyl Pyrrolidines and Cyclopentanes
Vila, Jordi,Vinardell, Roger,Solà, Miquel,Pla-Quintana, Anna,Roglans, Anna
supporting information, p. 206 - 217 (2021/11/17)
The cascade cyclization reactions of 1,5-bisallenes grant access to a great variety of products by precisely tuning the catalyst system and/or the reagents involved. Herein, we present our findings that 1,5-bisallenes react with two molecules of dimethyl acetylenedicarboxylate to afford, in a completely diastereoselective manner, cis-3,4-arylvinyl pyrrolidines and cyclopentanes. DFT calculations have been used to postulate a mechanism for the developed reaction which encompasses a [2+2+2] cycloaddition reaction of the two alkynes and the external double bond of one allene, followed by a cycloisomerization involving the internal double bond of the second allene. (Figure presented.).
Cyclotrimerization of alkynes catalyzed by a self-supported cyclic tri-nuclear nickel(0) complex with α-diimine ligands
Shen, Lingyi,Zhao, Yanxia,Luo, Qiong,Li, Qian-Shu,Liu, Bin,Redshaw, Carl,Wu, Biao,Yang, Xiao-Juan
supporting information, p. 4643 - 4649 (2019/04/05)
A cyclic tri-nuclear α-diimine nickel(0) complex [{Ni(μ-LMe-2,4)}3] (2) was synthesized from a “pre-organized”, trimerized trigonal LNiBr2-type precursor [Ni3(μ2-Br)3(μ3-Br)2(LMe-2,4)3]·Br (1; LMe-2,4 = [(2,4-Me2C6H3)NC(Me)]2). In complex 2, the α-diimine ligands not only exhibit the normal N,N′-chelating mode, but they also act as bridges between the Ni atoms through an unusual π-coordination of a C═N bond to Ni. Complex 2 is able to catalyze the cyclotrimerization of alkynes to form substituted benzenes in good yield and regio-selectivity for the 1,3,5-isomers, which is found to vary with the nature of the alkyne employed. This complex represents a convenient self-supported nickel(0) catalyst with no need for additional ligands and reducing agent.
