Synthesis of 2-Tetrazolylmethyl-2,3,4,9-tetrahydro-1H-β-carbolines by a One-Pot Ugi-Azide/Pictet–Spengler Process

Abstract

A series of novel 2-tetrazolylmethyl-2,3,4,9-tetrahydro-1H-β-carbolines were prepared in good to excellent overall yields by an efficient MW-assisted one-pot Ugi-azide/Pictet-Spengler process. This work describes the first synthesis of compounds including both 1,5-disubstituted 1H-tetrazole and 2,3,4,9-tetrahydro-1H-β-carboline heterocyclic systems.

Tetrazoles via Multicomponent Reactions

“…El Kaïm et al 286 first prepared an array of tetrahydro-1 H -β-carboline-tetrazoles in excellent overall yields using the UT/Pictet–Spengler reaction sequence. Tryptamine was used as a common starting material in the UT reaction ( 129 ), and the subsequent Pictet–Spengler reaction was performed with formaldehyde to form a series of 2-tetrazolylmethyl-2,3,4,9-tetrahydro-1 H -β-carbolines 130 either under refluxing conditions in methanol/toluene or under microwave conditions in the same reaction solvent with generally good to excellent yields (Scheme 50).…”

Combined isocyanide-based multi-component Ullmann-type reaction: an efficient access to novel nitrogen-containing pentacyclic compounds

“…Methanol proved to be the most optimal solvent for this reaction compared to DMF, CH 3 CN, and toluene (entries 8-10). It must be noted that no reaction was observed in the absence of ligand and copper salts, which completely ruled out S N Ar pathway (entries [11][12]. In addition, the yield decreased when the reaction was performed at lower temperatures (entry 13).…”

“…1). Thus, assembly of such a complex structures via effective and fast synthetic routes like multi-component reactions remains as a hot topic in organic chemistry [7][8][9][10][11][12][13].…”

Synthesis of Polyheterocyclic Dimers Containing Restricted and Constrained Peptidomimetics via IMCR-Based Domino/Double CuAAC Click Strategy

“…Our ongoing research program focuses on the design of new or novel, rapid, convergent, ecofriendly, and efficient post-IMCR/transformation strategies in consecutive [32][33][34][35][36][37][38] or domino manner [39][40][41] toward the synthesis of novel molecules containing conformationally restricted and/or constrained peptidomimetics. Recently, we reported the first ultrasound-assisted green one-pot synthesis of molecules containing privileged restricted peptidomimetics via this strategy: post-IMCR transformation/ Copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction employing a green alternative energy source [42].…”