Palladium- and copper-mediated N-aryl bond formation reactions for the synthesis of biological active compounds

• Carolin Fischer and
• Burkhard Koenig

Beilstein J. Org. Chem. 2011, 7, 59–74, doi:10.3762/bjoc.7.10

• catalytic synthetic sequence is an inexpensive and efficient route to the target compounds (Scheme 12) [64]. A three-component coupling reaction of 2-bromobenzenethiol 57, a primary amine 58 and 1-bromo-2-iodobenzenes 59, also targeting promazine derivatives 60, was successfully under palladium catalysis

One-pot three-component synthesis of quinoxaline and phenazine ring systems using Fischer carbene complexes

• Priyabrata Roy and
• Binay Krishna Ghorai

Beilstein J. Org. Chem. 2010, 6, No. 52, doi:10.3762/bjoc.6.52

• Priyabrata Roy Binay Krishna Ghorai Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103, India 10.3762/bjoc.6.52 Abstract One-pot three-component coupling of o-alkynylheteroaryl carbonyl derivatives with Fischer carbene complexes and dienophiles leading to

• ] using palladium catalyzed Sonogashira coupling reactions as depicted in Scheme 2. Iodoketone 6A was prepared in 80% yield from (3-chloro-2-pyrazinyl)phenylmethanone [35] by halogen exchange with NaI in acetonitrile. The three component coupling reaction of pyrazinyl ketone 1A, carbene complex 2 and N

• quinoxaline derivative 5b as the sole product after exposure to mild acid. The three component coupling reaction of o-alkynyl quinoxaline carbonyl derivative 1C, carbene complex 2 and N-phenylmaleimide/N-methylmaleimide was also examined (Table 1, entry 3 & 4). In these cases, tandem generation and trapping

Radical carbonylations using a continuous microflow system

• Takahide Fukuyama,
• Md. Taifur Rahman,
• Naoya Kamata and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2009, 5, No. 34, doi:10.3762/bjoc.5.34

• pressurized carbon monoxide gas. Good to excellent yields of carbonylated products were obtained via radical formylation, carbonylative cyclization and three-component coupling reactions, using tributyltin hydride or TTMSS as a radical mediator. Keywords: continuous flow system; microreactor; radical

• able to obtain the desired six-membered ring lactam 8 in good yield (entry 4). Using a similar microflow system, we then carried out a three-component coupling reaction comprised of 1-iodooctane (9), CO, and methyl vinyl ketone in the presence of tributyltin hydride [24], which also worked well to give

• acyl radical traps (entries 6 and 7 ). Gratifyingly, in both cases, good yields of the three-component coupling products were formed by using reduced CO pressure. Conclusion We have developed a facile platform to conduct radical carbonylation under CO pressure in a flow system comprised of a T-shaped

Cobalt(II) chloride catalyzed one-pot synthesis of α-aminonitriles

• Surya K. De

Beilstein J. Org. Chem. 2005, 1, No. 8, doi:10.1186/1860-5397-1-8

• , efficient, and practical method for the synthesis of α-aminonitriles through a one-pot three component coupling of aldehydes, amines, and potassium cyanide using a catalytic amount of cobalt(II) chloride. The major feature of this method is that it is truly a one-pot protocol that does not need a separate