Synthesis of functionalized spiro[indoline-3,4’-pyridines] and spiro[indoline-3,4’-pyridinones] via one-pot four-component reactions

• Li-Juan Zhang,
• Qun Wu,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2013, 9, 846–851, doi:10.3762/bjoc.9.97

• arylamines and other primary amines. Keywords: 1,4-dihydropyridine; electron-deficient alkyne; four-component reaction; isatin; one-pot reaction; spiro compound; Introduction β-Enaminones and β-enamino esters represent important synthetic building blocks for the development of versatile carbon–carbon bond

• functionalized spiro[indole-3,4’-pyridines] via the four-component reaction prompted us to study the reaction scope further [25]. Another widely used electron-deficient alkyne reagent, methyl propiolate, was utilized to replace dimethyl acetylenedicarboxylate as one component. The addition reaction of aniline to

• very clear. Conclusion In summary, we have successfully developed a one-pot four-component reaction of arylamines, methyl propiolate, isatin and malononitrile or ethyl cyanoacetate with triethylamine as base catalyst. This reaction can proceed smoothly under mild conditions to afford the functionalized

Recent advances in transition-metal-catalyzed intermolecular carbomagnesiation and carbozincation

• Kei Murakami and
• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 278–302, doi:10.3762/bjoc.9.34

• allylmagnesiation of alkynyl sulfone. Copper-catalyzed four-component reaction of alkynyl sulfoxide with alkylzinc reagent, diiodomethane, and benzaldehyde. Rhodium-catalyzed reaction of aryl alkynyl ketones with arylzinc reagents. Allylmagnesiation of propargyl alcohol, which provides the anti-addition product

Synthesis of spiro[dihydropyridine-oxindoles] via three-component reaction of arylamine, isatin and cyclopentane-1,3-dione

• Yan Sun,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2013, 9, 8–14, doi:10.3762/bjoc.9.2

• ] derivatives in moderate yields (Scheme 1a) [15]. In order to explore the generality of this four-component reaction, the reactivity of the other cyclic 1,3-diketones was also investigated. In an exploratory experiment, the four-component reaction of p-methoxyaniline, dimethyl acetylenedicarboxylate, 1-benzyl

The multicomponent approach to N-methyl peptides: total synthesis of antibacterial (–)-viridic acid and analogues

• Ricardo A. W. Neves Filho,
• Sebastian Stark,
• Bernhard Westermann and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2012, 8, 2085–2090, doi:10.3762/bjoc.8.234

• strategies and affords the optically active natural product in 20% overall yield over six steps. A more economical approach with only four steps leads to the similarly active racemate by utilizing a Ugi four-component reaction (Ugi-4CR) as the key transformation. A small library of viridic acid analogues is

• a bidirectional sequence from the least- to the most-reactive amine (NMe-Val < H-Ant-OBn < H-Gly) to yield the protected tetrapeptide 2 (Scheme 1a). Alternatively, a multicomponent (MCR) approach based on a Ugi four-component reaction (Ugi-4CR) of dipeptide 3, isobutyraldehyde, methylamine and

Amines as key building blocks in Pd-assisted multicomponent processes

• Didier Bouyssi,
• Nuno Monteiro and
• Geneviève Balme

Beilstein J. Org. Chem. 2011, 7, 1387–1406, doi:10.3762/bjoc.7.163

• another allenic unit. After a new transmetalation step with the boronic acid, the active catalytic species can be released and entered into a new catalytic cycle (Scheme 13). Imine as a nucleophilic partner A tandem four-component reaction allowing access to 1,2-dihydroisoquinolin-1-ylphosphonates 26 was

• -dihaloarene partner and the corresponding polysubstituted indoles were isolated in good yields as single regioisomers (Scheme 23). Based on this concept, Alper and coworkers reported the synthesis of isoindolin-1-one derivatives 53 through a four-component reaction starting from ortho-dihaloarenes and

• stereoselectivity. A four-component reaction was further developed through an in situ post C–B arylation by adding a second aryl iodide, with Cs2CO3 and water, to the newly formed alkenylboronate 78. The subsequent Suzuki–Miyaura coupling led to the formation of 2,3-diarylated amines 79 and the best results were

Novel synthesis of pseudopeptides bearing a difluoromethyl group by Ugi reaction and desulfanylation

• Jingjing Wu,
• Hui Li and
• Song Cao

Beilstein J. Org. Chem. 2011, 7, 1070–1074, doi:10.3762/bjoc.7.123

• triglyceride transfer protein (MTP) and useful for the treatment of obesity and atherosclerosis (Figure 1) [20]. Among the protocols for the preparation of pseudopeptide derivatives, the Ugi four-component reaction offers significant advantages over conventional linear-step synthesis [21]. Various fluorinated

• building blocks have been used in the Ugi four-component reaction to construct a fluorinated compound library [22][23][24][25]. Our group has always been interested in developing efficient methods for the preparation of difluoromethyl-containing compounds through multicomponent reactions [26][27][28][29

Synthesis of dihydrophenanthridines by a sequence of Ugi-4CR and palladium- catalyzed intramolecular C-H functionalization

• Florence Bonnaterre,
• Michèle Bois-Choussy and
• Jieping Zhu

Beilstein J. Org. Chem. 2008, 4, No. 10, doi:10.3762/bjoc.4.10

• . Introduction Multicomponent reactions (MCRs) offer a unique way to generate efficiently libraries of complex molecules with high degree of diversity [1][2]. Among them, the Ugi four component reaction (Ugi-4CR) is without doubt one of the most powerful transformations that has been extensively investigated for

• Scheme 1. The Ugi four-component reaction between an o-iodobenzaldehyde 2, an aniline 3, an isocyanide 4 and a carboxylic acid 5 should afford an α-acetamido-α-phenylacetamide 6, which upon palladium-catalyzed C-H activation process should provide dihydrophenanthridine 1 [15][16][17][18][19][20][21

• developed an efficient palladium-catalyzed intramolecular CH-arylation reaction leading, under ligandless conditions, to dihydrophenanthridines in good to excellent yields. In combination with the Ugi four-component reaction, this medicinally important heterocycle can be easily prepared in two steps from