The Oxidative Mannich Reaction Catalyzed by Dirhodium Caprolactamate

Abstract

Dirhodium caprolactamate [Rh2(cap)4] is a highly effective catalyst for the oxidative Mannich reaction. The reaction proceeds via C-H oxidation of a tertiary amine followed by nucleophilic capture. This green transformation is conducted in protic solvent using inexpensive T-HYDRO (70% t-BuOOH in water). Synthetically valuable gamma-aminoalkyl butenolides are obtained.

Solvent-Free Cross-Dehydrogenative Coupling Reactions under High Speed Ball-Milling Conditions Applied to the Synthesis of Functionalized Tetrahydroisoquinolines

“…Elution of the column with PE/EtOAc (15: 1) = 16.4,4.8,4.8 Hz,1H) ; 13 C NMR (CDCl 3 , 100 MHz, ppm) δ 148. 3,135.1,132.8,129.4,129.1,128.0,126.9,126.6,119.3,115.0,78.8,58.2,42.1,26.6. Anal.…”

“…9, 127.3, 127.1, 126.2, 122.9, 119.6, 116.6 (2C), 88.6, 84.8, 52.4, 43.6, 29.1. 1-(p-Tolylethynyl)-2-phenyl-1,2,3,4-tetrahydroisoquinoline (5b): colorless crystal; mp 56.9−61.1°C; IR (KBr) 3048,3024,2950,2916,2849,2202,1901,1598,1508,1453,1375,1263,1216, 1020, 934 cm −1 ; 1 H NMR (400 MHz, CDCl 3 , ppm) δ 7.39−7.25 (m, 3H), 7.24−7.13 (m, 5H), 7.10 (d, J = 8.4 Hz, 2H), 7.00 (d, J = 8.0 Hz, 2H), 6.87 (dd, J 1 = J 2 = 7.2 Hz, 1H), 5.62 (s, 1H), 3.78−3.62 (m, 2H), 3.13 (ddd, J = 16.0, 10.0, 6.0 Hz, 1H), 2.97 (ddd, J = 16.0, 3.6, 3.6 Hz, 1H), 2.28 (s, 3H); 13 C NMR (CDCl 3 , 100 MHz, ppm) δ 149. 3,137.8,135.3,134.2,131.4 (2C),128.9 (2C),128.7,128.6 (2C),127.2,127.0,126.1,122.9,119.8,119.4,116.5 (2C),87.8,84.8,52.3,43.5,29.0,21.5;MS (ESI) 1-((4-Fluorophenyl)ethynyl)-2-phenyl-1,2,3,4-tetrahydroisoquinoline (5c): colorless crystal; mp 115. 5−116.1°C;IR (KBr) 3064, 3028, 2992, 2924, 2843, 1597, 1504, 1450, 1370, 1279, 1204, 1154, 1138, 1032, 1016, 935 cm −1 ; 1 H NMR (400 MHz, ...…”

Ruthenium‐Catalyzed Alkylation of Indoles with Tertiary Amines by Oxidation of a sp3 CH Bond and Lewis Acid Catalysis

“…[4] Mechanism of the ruthenium porphyrin-or RuCl 3 -catalyzed oxidative coupling reaction of tertiary amines with indoles using TBHP as oxidant: Based on the results presented in …”

“…[4] Vogel and co-workers reported an FeCl 2 -catalyzed oxidative C À C cross-coupling of tertiary amines with terminal alkynes Abstract: Ruthenium porphyrins (particularly [Ru(2,6-Cl 2 tpp)CO]; tpp = tetraphenylporphinato) and RuCl 3 can act as oxidation and/or Lewis acid catalysts for direct C-3 alkylation of indoles, giving the desired products in high yields (up to 82 % based on 60-95 % substrate conversions). These ruthenium compounds catalyze oxidative coupling reactions of a wide variety of anilines and indoles bearing electron-withdrawing or electron-donating substituents with high regioselectivity when using tBuOOH as an oxidant, resulting in the alkylation of N-arylindoles to 3-{[(N-aryl-N-alkyl)amino]methyl}indoles (yield: up to 82 %, conversion: up to 95 %) and the alkylation of N-alkyl or N-H indoles to 3-[p-(dialkylamino)benzyl]indoles (yield: up to 73 %, conversion: up to 92 %).…”

CHAPTER 5. Cross Dehydrogenative Coupling Reactions by Ball Milling

“…Other transition metal catalyzed oxidation systems such as rhodium-T-HYDRO (70% in water), 5 iron-( t BuO) 2 / t BuOOH, 6 vanadium-t BuOOH, 7 and ruthenium-O 2 8 systems also showed high activities in CDC reactions. In addition, the reaction could proceed in the absence of oxidant by using platinum as catalyst.…”