(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

Free-radical cyclization approach to polyheterocycles containing pyrrole and pyridine rings

• Ivan P. Mosiagin,
• Olesya A. Tomashenko,
• Dar’ya V. Spiridonova,
• Mikhail S. Novikov,
• Sergey P. Tunik and
• Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2021, 17, 1490–1498, doi:10.3762/bjoc.17.105

• skeletons that are inaccessible via Pd-catalyzed cyclization. Keywords: arylation; pyridine; pyrrole; radical cyclization; tris(trimethylsilyl)silane; Introduction Polycyclic heteroaromatic molecules, which have a tunable electronic structure and excellent self-assembling properties, are highly desirable

• compounds are more expensive and less accessible than bromo-substituted analogs, we tried to accomplish the cyclization of pyridinium salt 1a using another radical mediator, tris(trimethylsilyl)silane (TTMSS) [31][32], which, moreover, is much less toxic than tributylstannane. Fortunately, free-radical

Organometallic vs organic photoredox catalysts for photocuring reactions in the visible region

• Aude-Héloise Bonardi,
• Frédéric Dumur,
• Guillaume Noirbent,
• Jacques Lalevée and
• Didier Gigmes

Beilstein J. Org. Chem. 2018, 14, 3025–3046, doi:10.3762/bjoc.14.282

• catalyst can react through an oxidative or a reductive cycle as presented in Figure 1. Herein, we will present four additives that can be used in combination with a photoredox catalyst to initiated photopolymerization (Scheme 1). As reduction agent, silanes such as tris(trimethylsilyl)silane (abbreviated

Preparation of phosphines through C–P bond formation

• Iris Wauters,
• Wouter Debrouwer and
• Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

• formed exclusively and isolated as the phosphine sulfides 140 to prevent lower yields by oxidation to the corresponding oxides. The phosphines 141 were obtained by radical reduction of 140 with tris(trimethylsilyl)silane (TTMSS). However, when Kumaraswamy et al. explored the copper-catalyzed

Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization

• Jacques Lalevée,
• Sofia Telitel,
• Pu Xiao,
• Marc Lepeltier,
• Frédéric Dumur,
• Fabrice Morlet-Savary,
• Didier Gigmes and
• Jean-Pierre Fouassier

Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83

• . These PICs are typically used (see below) in combination with various additives (see Figure 3 below) in three-component photoinitiating systems, e.g., based PIC/iodonium salt (or sulfonium salt)/tris(trimethylsilyl)silane (or N-vinylcarbazole) or PIC/amine/alkyl halide. Also, relatively high intensity

• system based on Scheme 4 involving Ru(bpy)32+ as PIC, Ph2I+ as eA and a silane R3SiH (e.g., tris(trimethylsilyl)silane TTMSS) as Add is detailed in Scheme 6. A phenyl radical is generated (previously noted Rad-m in Scheme 4). A silyl radical R3Si• (noted Rad-1 above) and a silylium R3Si+ are formed

A construction of 4,4-spirocyclic γ-lactams by tandem radical cyclization with carbon monoxide

• Mitsuhiro Ueda,
• Yoshitaka Uenoyama,
• Nozomi Terasoma,
• Shoko Doi,
• Shoji Kobayashi,
• Ilhyong Ryu and
• John A. Murphy

Beilstein J. Org. Chem. 2013, 9, 1340–1345, doi:10.3762/bjoc.9.151

• 2a to 53% was achieved by changing the mediator from Bu3SnH to TTMSS [tris(trimethylsilyl)silane]. The tandem spirocyclization with CO was investigated with several 2-iodoaryl compounds having an allyl azide moiety. Results are summarized in Table 1. The reaction of N-(2-(azidomethyl)allyl)-N-(2-iodo

• -iodophenyl)acrylamide (1f) (150.0 mg, 0.36 mmol), AIBN (2,2’-azobisisobutyronitrile, 17.7 mg, 0.11 mmol), TTMSS ([tris(trimethylsilyl)silane], 178.3 mg, 0.72 mmol) and THF (17.9 mL; 0.02 M) were placed in a 50 mL stainless steel autoclave. The autoclave was closed, purged three times with CO, pressurized

Preparation of optically active bicyclodihydrosiloles by a radical cascade reaction

• Koichiro Miyazaki,
• Yu Yamane,
• Ryuichiro Yo,
• Hidemitsu Uno and
• Akio Kamimura

Beilstein J. Org. Chem. 2013, 9, 1326–1332, doi:10.3762/bjoc.9.149

• 10.3762/bjoc.9.149 Abstract Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an α,β-unsaturated ester, forming an α

• : bicyclodihydrosilole; free radical; radical cascade reaction; SHi reaction; tris(trimethylsilyl)silane; Introduction Radical cyclization occupies a unique position in organic synthesis because it is a useful reaction for the construction of cyclic molecules [1][2][3][4][5][6][7][8][9][10]. The radical cascade

• methylthiyl radical also undergoes such a radical cascade reaction to stereoselectively give bicyclic dihydrothiophenes [16]. We expected that tris(trimethylsilyl)silane (Me3Si)3SiH [17], which is a well-known alternative to Bu3SnH in radical reactions [18][19][20][21][22], would be a good promoter of a

Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

• reduction of chlorodiphenylphosphine with tris(trimethylsilyl)silane followed by condensation of the resulting diphenylphosphine with the remaining chlorophosphine (Scheme 16, equation 1 and 2). An aryl radical reacts with tetraphenyldiphosphine to liberate a diphenylphosphanyl radical, which abstracts

• hydrogen from tris(trimethylsilyl)silane to sustain the chain propagation (Scheme 16, equation 3–5). The in situ formations of diphenylphosphine and of tetraphenyldiphosphine can exclude the handling of pyrophoric diphenylphosphine and air-sensitive tetraphenyldiphosphine. The user-friendly conditions are

Some aspects of radical chemistry in the assembly of complex molecular architectures

• Béatrice Quiclet-Sire and
• Samir Z. Zard

Beilstein J. Org. Chem. 2013, 9, 557–576, doi:10.3762/bjoc.9.61

• encapsulated in the two addition reactions presented in Scheme 7 [22]. β-Lactam xanthates such as 31 and 33 can be readily added without harm to the fragile azetidinone motif and, if desired, the xanthate group may be reduced off by a number of methods, the mildest perhaps relying on tris(trimethylsilyl)silane

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

• demonstrated by our group [4][5][6] as well as others [7][8][9][10][11]. In our recent report, we demonstrated that excellent thermal efficiency of the microflow system would lead to effective execution of tin hydride and TTMSS (tris(trimethylsilyl)silane)-mediated radical reduction and cyclization reactions

• 2,5-tridecandione (10) in 78% yield (entry 5). Since tris(trimethylsilyl)silane (TTMSS) delivers a hydrogen atom to a carbon-centered radical at a slower rate than tributyltin hydride [25], carbonylation reactions with TTMSS can be carried out at lower CO pressure without being plagued by the