1100051-11-3Relevant articles and documents
Pd-Catalyzed One-Pot Stepwise Synthesis of Benzo[b][1,6]naphthyridines from 2-Chloroquinoline-3-carbonitriles Using Sulfur and Amines As Nucleophiles
Kumar, Ritush,Asthana, Mrityunjaya,Singh, Radhey M.
, p. 11531 - 11542 (2017/11/10)
A palladium-catalyzed one-pot stepwise coupling-annulation reaction of 2-chloroqunoline-3-carbonitriles enabled the direct synthesis of sulfur-substituted benzo[b][1,6]naphthyridines via multiple bond formation. The reaction provided an unusual mode for cyclization as sodium sulfide, a soft nucleophile, preferred to attack on the carbon of the nitrile group rather than on the C-C triple bond. The developed chemistry was extended with the secondary amines as nucleophiles to afford nitrogen-substituted benzo[b][1,6]naphythyridines while primary amines afforded hydroamination products. The hydromination products were transformed to benzo[b][1,6]naphthyridones via a base-mediated cyclization reaction. The developed protocol features inexpensive and easily synthesizable starting materials, easy operations, and a high efficiency and tolerance to a broad range of substrates.
Palladium-catalyzed one-pot synthesis of benzo[b][1,6]naphthyridines via Sonogashira coupling and annulation reactions from 2-chloroquinoline-3- carbonitriles
Singh, Radhey M.,Kumar, Ritush,Sharma, Neha,Asthana, Mrityunjaya
, p. 9443 - 9450 (2013/10/08)
Palladium-catalyzed one-pot synthesis of 1,3-disubstituted benzo[b][1,6]naphthyridines and [1,6]naphthyridines has been described from easily accessible precursors, 2-chloroquinoline-3-carbonitriles and 2-chloropyrido-3-carbonitrile via sequential additions of palladium-catalyst for Sonogashira-coupling and the following annulations in good to excellent yields. A plausible mechanism for annulation is discussed.
Copper-free Sonogashira coupling of 2-chloroquinolines with phenyl acetylene and quick annulation to benzo[b][1,6]naphthyridine derivatives in aqueous ammonia
Chandra, Atish,Singh, Bhawana,Upadhyay, Shraddha,Singh, Radhey M.
experimental part, p. 11680 - 11685 (2009/04/11)
An efficient copper-free Sonogashira coupling of 2-chloroquinolines with phenyl acetylene to 2-ethynylquinolines is described. We further discussed the one pot facile annulation of 2-alkynylquinoline-3-carboxaldehydes to 3-phenylbenzo[b][1,6]naphthyridines in aqueous ammonia in excellent yield.
