Stille coupling approaches for the synthesis of 8-aryl guanines

Arsenyan, Pavel; Ikaunieks, Martins; Belyakov, Sergey

doi:10.1016/j.tetlet.2006.12.020

Cited by 16 publications

(9 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Only Stille conditions (entry 3, Table ) with triphenylbismuth (5%) both successfully and reproducibly allowed cross-coupling of 14 with stannylthiophene (affording 15 in 66% yield). Presumably, the longer Bi–Pd bond (versus the P–Pd bond) facilitates activation of the catalyst and reduces the reaction time . The same conditions were attempted (Scheme ) for coupling 14 and a bis(trimethylstannylthienyl)benzothiadiazole derivative 17 (prepared efficiently from 4,7-di(thiophen-2-yl)benzo[ c ][1,2,5]thiadiazole 16 ) to provide 1c directly; however, these conditions led to decomposition of the benzothiadiazole reagent.…”

Section: Resultsmentioning

confidence: 98%

Synthesis, Optical Properties, and Electronic Structures of Nucleobase-Containing π-Conjugated Oligomers

et al. 2015

View full text Add to dashboard Cite

The molecular recognition properties of the nucleobases instruct the formation of complex three-dimensional architectures in natural and synthetic systems; relatively unexplored is their use as building blocks for π-conjugated materials where they might mutually tune electronic and supramolecular structures. Toward this goal, an introductory set (1a-d and 2a-d) of six purine-terminated and two pyrimidine-terminated π-conjugated oligomers has been synthesized and used to develop experimental electronic and photophysical structure-property trends. Unlike 2,2':5',2″-terthiophene (TTT) derivatives 2a-d, intramolecular charge transfer dominates oligomers 1a-d bearing a 4,7-bisthienylbenzothiadiazole (TBT) spacer due to the strong electron-accepting ability of its benzothiadiazole (BTD) ring. The resulting donor-acceptor-donor systems feature lower HOMO-LUMO gaps than the terthiophene-linked nucleobases (ΔE(g) ∼ 1.8 eV vs 2.4 eV based on electrochemical measurements), and the lowest so far for π-conjugated molecules that include nucleobases within the π-framework. Experiments reveal a dependence of photophysical and electronic structure on the nature of the nucleobase and are in good agreement with theoretical calculations performed at the B3LYP/6-31+G** level. Overall, the results show how nucleobase heterocycles can be installed within π-systems to tune optical and electronic properties. Future work will evaluate the consequences of these information-rich components on supramolecular π-conjugated structure.

show abstract

Section: Resultsmentioning

confidence: 98%

Synthesis, Optical Properties, and Electronic Structures of Nucleobase-Containing π-Conjugated Oligomers

et al. 2015

View full text Add to dashboard Cite

show abstract

“…One day heating of corresponding stannanes with 1 in the presence of tetrakis(triphenylphosphino)palladium(0) in xylene at 130 C leads to the formation of 7 and 8 in medium yields. With the aim of reducing the reaction time and to activate the catalyst, a catalytic amount (7%) of triphenylarsine was added [24] due to the donor-acceptor AsePd bond being longer than PePd bond. As a result desired derivatives 7 and 8 were obtained in higher yields (75e79%) after only 2 h of heating.…”

Section: Chemistrymentioning

confidence: 99%

Synthesis, structure and cytotoxicity of 3-C, N, S, Se substituted benzo[b]selenophene derivatives

Arsenyan

Paegle

Belyakov

et al. 2011

European Journal of Medicinal Chemistry

Self Cite

View full text Add to dashboard Cite

“…It was found that the addition of AsPh 3 strongly reduces the reaction time and increases the yields (eq 21). 33 This effect of the addition of AsPh 3 is somewhat surprising, unless the reaction conditions lead to considerable phosphine oxidation; it might be worth trying Pd(AsPh 3 ) 4 as a catalyst, and chloride or bromide as a promoter of the oxidative addition step (chloride effect). 29 …”

Section: Application Of Asph 3 As Ligand In Catalysismentioning

confidence: 99%