Recent progress in the synthesis of pyrrolo[2,1-a]isoquinolines

Abstract

Pyrrolo[2,1-a]isoquinoline occurs frequently in a large number of bioactive natural products and pharmaceutically important molecules. Synthesis of pyrrolo[2,1-a]isoquinoline derivatives is an easy and useful way for producing artificial molecules with...

Synthesis of Pyrrolo[2,1-a]isoquinolines through Cu-Catalyzed Condensation/Addition/Oxidation/Cyclization Cascade

“…Furthermore, since pyrroloisoquinoline consists of two privileged frameworks, this skeleton can be regarded as special functionalized pyrrole or substituted isoquinoline. Thus, modified pyrrolo­[2,1- a ]­isoquinolines would have great application potential in various research fields …”

Green and Efficient Construction of Chromeno[3,4-c]pyrrole Core via Barton–Zard Reaction from 3-Nitro-2H-chromenes and Ethyl Isocyanoacetate

“…The chromenopyrrole moiety is present in a wide range of natural and synthetic compounds with a number of important useful properties [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Thus, chromeno[3,4- b ]pyrrole scaffold is the basis of the skeleton of type I lamellarin alkaloids isolated from marine mollusks, tunicates and sponges [ 1 , 2 ] ( Figure 1 ).…”

“…Pericyclic pyrrolo[3,4- c ]coumarin 4 emits blue light and may be tested as blue-light emitters with an electron-transporting ability [ 10 ] ( Figure 1 ). In view of the above, the development of methods for the synthesis of these classes of compounds is being carried out by various scientific groups, and the search for new effective approaches to the design of chromenopyrrole scaffolds continues [ 11 , 12 , 13 , 14 , 15 ].…”

Metal-free photoinduced alkylative [3 + 2] annulation of terminal alkynes with N-alkyl isoquinolin-2-iums by catalytic isoquinoline-based electron donor–acceptor complex

“…1 a – i As such, there is growing demand to develop efficient methods for straightforward construction of the pyrrolo[2,1- a ]isoquinoline scaffold. 2–6 Conventional methodologies generally involve two different modes of reactivity as the final step, including construction of a pyrrole framework on the existing isoquinoline ring 2–5 or assembly of an isoquinoline unit on the existing pyrrole ring. 6 Typically, approaches for construction of a pyrrole framework on the existing isoquinoline ring have been proven to be powerful and popular, and are focused on cycloaddition reactions with activated unsaturated hydrocarbons (such as alkynes, alkenes and allenes), including 1,3-dipolar cycloaddition reactions, electrocyclization, Michael/condensation reactions, Michael/substitution reactions, Michael/oxidative C–N coupling reactions and N -ylide-based annulation reactions.…”

“…6 Typically, approaches for construction of a pyrrole framework on the existing isoquinoline ring have been proven to be powerful and popular, and are focused on cycloaddition reactions with activated unsaturated hydrocarbons (such as alkynes, alkenes and allenes), including 1,3-dipolar cycloaddition reactions, electrocyclization, Michael/condensation reactions, Michael/substitution reactions, Michael/oxidative C–N coupling reactions and N -ylide-based annulation reactions. 2–5 These cycloaddition transformations often first require the conversion of isoquinolines and their derivatives into highly reactive isoquinolinium salts (ylides), 3,4 which thus enable cycloaddition with the activated unsaturated hydrocarbons to assemble pyrrolo[2,1- a ]isoquinoline frameworks. Despite these advances, such methods, and more specifically the methods that consist of an intermolecular annulation of isoquinolinium salts (ylides) with alkynes, remain underdeveloped.…”