One-pot synthesis of 2-arylated and 2-alkylated benzoxazoles and benzimidazoles based on triphenylbismuth dichloride-promoted desulfurization of thioamides

• Arisu Koyanagi,
• Yuki Murata,
• Shiori Hayakawa,
• Mio Matsumura and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155

• , the need for bases, and limited substrate scope. With the development of organobismuth chemistry, these compounds have been applied in various areas of science including biology and organic synthesis because they are normally non-toxic and exhibit unique biological activities [13][14][15][16][17][18

• initially focused on identifying the optimal experimental conditions for the synthesis of 2-phenylbenzoxazole (8a) using 2-aminophenol (1a) with benzothioamides 2–5 in the presence of organobismuth or organoantimony compounds 6 or 7. The results, including those for the screening of suitable ring-closure

• reagents, solvents, thioamides, and reagent ratios, are summarized in Table 1. We first performed the reaction of 1a (0.5 mmol) with N-phenylbenzothioamide (2a, 1.0 mmol) using organobismuth or organoantimony reagents 6 or 7 (1.0 mmol) in 1,2-dichloroethane (DCE) under aerobic conditions at 60 °C for 18 h

Synthesis of aryl cyclopropyl sulfides through copper-promoted S-cyclopropylation of thiophenols using cyclopropylboronic acid

• Emeline Benoit,
• Ahmed Fnaiche and
• Alexandre Gagnon

Beilstein J. Org. Chem. 2019, 15, 1162–1171, doi:10.3762/bjoc.15.113

• this method, particularly with respect to medicinal chemistry where expedient methods from easily accessible substrates are needed. Organobismuth compounds are organometallic reagents that possess a C–Bi bond and which can be synthesized from inexpensive and low-toxic bismuth salts [24][25]. Due to the

• borderline behavior of bismuth as a metal and a ligand, organobismuth species have been used as reagents and catalysts in a wide range of reactions. We reported a portfolio of methods for the construction of C–C [26][27][28][29], C–N [30] and C–O bonds [31][32][33] using triaryl- and trialkylbismuthines [34

• -cyclopropylate thiophenols 14, giving access to aryl cyclopropyl sulfides 1 (Scheme 2f) [38]. While this constituted the first example on the use of an organobismuth reagent in the construction of C(sp3)–S bonds, synthetically, the method showed limitations such as the need for a high excess of

Bi-mediated allylation of aldehydes in [bmim][Br]: a mechanistic investigation

• Mrunesh Koli,
• Sucheta Chatterjee,
• Subrata Chattopadhyay and
• Dibakar Goswami

Beilstein J. Org. Chem. 2018, 14, 2198–2203, doi:10.3762/bjoc.14.193

• the powder XRD analysis of the light yellow precipitate. Earlier, it has been reported [38][43] that the organobismuth halide generated in situ may act as a Lewis acid activator for the faster production of linear homoallylic alcohols. In the present case also, such a mechanism cannot be excluded

Evaluation of dispersion type metal···π arene interaction in arylbismuth compounds – an experimental and theoretical study

• Ana-Maria Preda,
• Małgorzata Krasowska,
• Lydia Wrobel,
• Philipp Kitschke,
• Phil C. Andrews,
• Jonathan G. MacLellan,
• Lutz Mertens,
• Marcus Korb,
• Tobias Rüffer,
• Heinrich Lang,
• Alexander A. Auer and
• Michael Mehring

Beilstein J. Org. Chem. 2018, 14, 2125–2145, doi:10.3762/bjoc.14.187

• and C–H···π interactions in organobismuth compounds and therefore the crystal structures are described and discussed in the following chapter. Please note that the term C–H···π is used as a structure descriptor rather than to describe a special type of bonding. Thus we follow the criticism given by

Photoinduced synthesis of unsymmetrical diaryl selenides from triarylbismuthines and diaryl diselenides

• Yohsuke Kobiki,
• Shin-ichi Kawaguchi,
• Takashi Ohe and
• Akiya Ogawa

Beilstein J. Org. Chem. 2013, 9, 1141–1147, doi:10.3762/bjoc.9.127

• absence of transition-metal catalysts. A variety of unsymmetrical diaryl selenides can be conveniently prepared by using this arylation method. Keywords: arylation; unsymmetrical diaryl selenide; free radical; organobismuth; photoinduced reaction; Introduction A number of organoselenium compounds are

• catalysts is desirable. On the other hand, triarylbismuthines are gaining interest as useful arylation reagents, because organobismuth compounds are nontoxic and have excellent reactivity, which has led to several applications in organic synthesis [33]. Therefore, numerous transition-metal-catalyzed

• coupling reactions with organobismuth compounds have been reported [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53]. Although triphenylbismuthine can generate a phenyl radical [33][54] in the absence of a radical initiator simply by photoirradiation, few arylation reactions

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

• (IV) triacetates [33] and pentavalent organobismuth reagents [34] have also been used as aryl donors for copper-mediated C–N couplings. Further improvement of N-arylation conditions was achieved by the use of arylboronic acids. The reagents are not sensitive to air; the reaction proceeds at room