Concise Synthesis of Annulated Pyrido[3,4-b]indoles via Rh(I)-Catalyzed Cyclization.
The synthesis of pyridines bearing multiple ring fusions poses a considerable challenge for organic chemists. To address this problem, we describe the synthesis of a small library of pyrido[3,4-b]indoles via an efficient, five-step sequence. The key transformation is a Rh(I)-catalyzed [2 + 2 + 2] cyclization that forms three rings in one reaction flask. Our method is high yielding, accommodates a variety of functional groups, and suffers no entropic costs as ring size increases.
Department of Chemistry and Biochemistry, Providence College , 1 Cunningham Square, Providence, Rhode Island 02918, United States.
Jonathan G
JG
Varelas
Department of Chemistry and Biochemistry, Providence College , 1 Cunningham Square, Providence, Rhode Island 02918, United States.
Satyam
S
Khanal
Department of Chemistry and Biochemistry, Providence College , 1 Cunningham Square, Providence, Rhode Island 02918, United States.
Michael A
MA
O'Donnell
Department of Chemistry and Biochemistry, Providence College , 1 Cunningham Square, Providence, Rhode Island 02918, United States.
Seann P
SP
Mulcahy
D002384:Catalysis; D003500:Cyclization; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011725:Pyridines / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*
D006576:Heterocyclic Compounds, 4 or More Rings; D007211:Indoles; D011725:Pyridines; D012238:Rhodium