Synthesis of purines and adenines containing the hexafluoroisopropyl group

• Viacheslav Petrov,
• Rebecca J. Dooley,
• Alexander A. Marchione,
• Elizabeth L. Diaz,
• Brittany S. Clem and
• William Marshall

Beilstein J. Org. Chem. 2020, 16, 2739–2748, doi:10.3762/bjoc.16.224

• investigational therapeutic agents, including antitumorals and antivirals […]” [8]. Interestingly, most fluorine-containing benzimidazoles contain the fluorinated substituent either on the aromatic ring or on a side chain connected to the aromatic ring; examples of benzimidazoles containing a fluoroalkyl group

• caffeine analogue, modified by the attachment of two CF3 groups to the methyl group. This is the first example of an introduction of a fluoroalkyl group bigger than CF3 or CF2H into a theophylline (7) molecule, since known examples of fluorinated caffeine derivatives are limited to 7-trifluoromethyl

Chan–Evans–Lam N1-(het)arylation and N1-alkеnylation of 4-fluoroalkylpyrimidin-2(1H)-ones

• Viktor M. Tkachuk,
• Oleh O. Lukianov,
• Mykhailo V. Vovk,
• Isabelle Gillaizeau and
• Volodymyr A. Sukach

Beilstein J. Org. Chem. 2020, 16, 2304–2313, doi:10.3762/bjoc.16.191

• corresponding pyrimidines. An efficient C–N bond-forming process is also observed by using boronic acid pinacol esters as coupling partners in the presence of Cu(II) acetate and boric acid. The 4-fluoroalkyl group on the pyrimidine ring significantly assists in the formation of the target N1-substituted

• products, in contrast to the 4-methyl and 4-unsubstituted substrates which do not undergo N1-arylation under similar reaction conditions. Keywords: C–N cross-coupling; Chan–Evans–Lam reaction; pyrimidin-2(1Н)-ones; fluoroalkyl group; boronic acids; Introduction The catalytic formation of C–N bonds in the

• 9d,e. Thus, the presence of the electron-withdrawing 4-fluoroalkyl group in pyrimidones 1 is a significant structural factor playing a major role in the overall success of the Chan–Evans–Lam reaction, most likely due to related increase in NH-acidity of the heterocyclic system. The ester group and

Regioselective cobalt(II)-catalyzed [2 + 3] cycloaddition reaction of fluoroalkylated alkynes with 2-formylphenylboronic acids: easy access to 2-fluoroalkylated indenols

• Tatsuya Kumon,
• Miroku Shimada,
• Jianyan Wu,
• Shigeyuki Yamada and
• Tsutomu Konno

Beilstein J. Org. Chem. 2020, 16, 2193–2200, doi:10.3762/bjoc.16.184

• proton Ha of Int-3b is the same as, or higher than the hydroxy group of Int-4b due to the electron-withdrawing effect of the fluoroalkyl group. It should be noted that this process is probably accelerated by 2-propanol or H2O, which is explained by the results that the most 3-fluoroalkylated indenol 4aA

• to the electron-withdrawing ability of the fluoroalkyl group. The Int-5b species undergoes protonation at the carbon bonded to the fluoroalkyl group, giving the enol Int-6b. Finally, the enol Int-6b produces the 3-fluoroalkylated indanone 5 via keto–enol tautomerism. Conclusion In conclusion, we

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• , spirocyclic derivative 33e was formed in a significantly lower yield. Surprisingly, a subtle change of the fluoroalkyl group from a CF3 group to a CHF2 group completely inhibited the reaction. Within the frame of a broader study, our group reported a single example of an intramolecular PKR using an Ellman’s

• , for alkynes 58b,c the opposite regiochemistry was found. Finally, the use of alkyne 58d with two electron-withdrawing groups resulted in the regioselective formation of product 59d in excellent yield, indicating an inherent trend of the fluoroalkyl group to occupy the α-position regardless of the

Formal preparation of regioregular and alternating thiophene–thiophene copolymers bearing different substituents

• Atsunori Mori,
• Keisuke Fujita,
• Chihiro Kubota,
• Toyoko Suzuki,
• Kentaro Okano,
• Takuya Matsumoto,
• Takashi Nishino and
• Masaki Horie

Beilstein J. Org. Chem. 2020, 16, 317–324, doi:10.3762/bjoc.16.31

• fluoroalkyl group and a branched oligosiloxane unit in hexanes was noted. XRD analysis of the copolymer 6c, bearing branched oligosiloxane and methyl groups, was carried out. Two remarkable peaks were observed at 2θ = 3.94° and 12.18°, respectively, as shown in Figure 2a. The result suggested that the thin

Nucleophilic fluoroalkylation/cyclization route to fluorinated phthalides

• Masanori Inaba,
• Tatsuya Sakai,
• Shun Shinada,
• Tsuyuka Sugiishi,
• Yuta Nishina,
• Norio Shibata and
• Hideki Amii

Beilstein J. Org. Chem. 2018, 14, 182–186, doi:10.3762/bjoc.14.12

• [3][4][5][6][7][8][9][10]. Selective incorporation of fluorine or a fluoroalkyl group into a molecule is a topic of significant interest in organic chemistry. Fluorinated phthalides are considered to be one of the most fascinating organofluorine compounds. However, to our best knowledge, there have

Progress in copper-catalyzed trifluoromethylation

• Guan-bao Li,
• Chao Zhang,
• Chun Song and
• Yu-dao Ma

Beilstein J. Org. Chem. 2018, 14, 155–181, doi:10.3762/bjoc.14.11

• ; trifluoromethylation; Introduction The fluorine atom has a strong electronegativity and a small atomic radius, and the incorporation of fluoroalkyl groups into molecules imparts a variety of features. The trifluoromethyl group, as the most significant common used fluoroalkyl group, could improve molecular properties

Synthesis of new triazole- based trifluoromethyl scaffolds

• Michela Martinelli,
• Thierry Milcent,
• Sandrine Ongeri and
• Benoit Crousse

Beilstein J. Org. Chem. 2008, 4, No. 19, doi:10.3762/bjoc.4.19

• . On the other hand, it is well known that the introduction of fluorine atoms or a fluoroalkyl group can greatly modify the physico-chemical features and thus the biological properties of a molecule (resistance to metabolic oxidation and hydrolysis, modification of pKa, hydrophobicity,...) [14][15][16