Rapid gas–liquid reaction in flow. Continuous synthesis and production of cyclohexene oxide

• Kyoko Mandai,
• Tetsuya Yamamoto,
• Hiroki Mandai and
• Aiichiro Nagaki

Beilstein J. Org. Chem. 2022, 18, 660–668, doi:10.3762/bjoc.18.67

• ratio of aldehyde and oxygen to 1:9. The liquid and gas phases were combined at a T-shaped mixer with a 1 mm inner diameter and flowed through a stainless-steel tube reactor immersed in heated silicon oil for reaction temperature control. The inner pressure was maintained at 0.9 MPa using a back

• with air in the flow microreactor A flow microreactor system consisting of a T-shaped micromixer, and one microtube reactor was used for epoxidation of cyclohexene with air. A solution of cyclohexene (0.065 M), isobutyraldehyde (0.195 M), and tridecane as an internal standard in 1,2-dichloroethane

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition

• Sivaraman Balasubramaniam,
• Sajith Vijayan,
• Liam V. Goldman,
• Xavier A. May,
• Kyra Dodson,
• Sweta Adhikari,
• Fatima Rivas,
• Davita L. Watkins and
• Shana V. Stoddard

Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59

• indole ring of TOI4 was also contorted upward, forming a T-shaped π–π interaction with Phe-207 while both the indole rings of TOI1 and TOI2 were shown to be flipped downward forming a T-shaped π–π interaction with Phe-208. TOI4 is the only diazine compound having two nitrogens directly next to each other

• -rev is tilted downward forming a T-shaped π–π interaction with Phe-208. In review of the computational results, the inclusion of the nitrogen atoms in the core ring structure of panobinostat produced compounds with predicted binding affinities similar to panobinostat. Thus, aiming to develop improved

Palladium-catalyzed synthesis and nucleotide pyrophosphatase inhibition of benzo[4,5]furo[3,2-b]indoles

• Hoang Huy Do,
• Saif Ullah,
• Alexander Villinger,
• Joanna Lecka,
• Jean Sévigny,
• Peter Ehlers,
• Jamshed Iqbal and
• Peter Langer

Beilstein J. Org. Chem. 2019, 15, 2830–2839, doi:10.3762/bjoc.15.276

• involved in hydrogen bonding were His380, Asn277, Ser378, Ser381, Tyr382, Lys391, Ser387 and Ser386. In addition, the study also showed binding with the zinc ion and π-interactions, in particular, π–π T-shaped and amide–π shaped coupling with Ser377 and Tyr382. The molecular docking study of compound 5c

• exhibited π–π T-shaped interactions connecting the indole and furan rings with Tyr340. However, π–alkyl linkage was observed between the benzofuran moiety of compound 5c and amino acid Lys295. The fluorine atom of the 4-fluorophenyl group was involved in the binding with the zinc ion and Ser377. Hydrogen

• . However, the zinc–metal interaction was exhibited by the substituted phenyl moiety on the indole ring. The oxygen atom of the furan ring of dual inhibitor 6e showed a single hydrogen bond with Phe548. Asp423 was found to be involved in two π–cation bindings with the indole ring, whereas π–π stacked, π–π T

A combinatorial approach to improving the performance of azoarene photoswitches

• Joaquin Calbo,
• Aditya R. Thawani,
• Rosina S. L. Gibson,
• Andrew J. P. White and
• Matthew J. Fuchter

Beilstein J. Org. Chem. 2019, 15, 2753–2764, doi:10.3762/bjoc.15.266

• consistent with our previous studies on 4pzH compared to 4pzMe [18], significantly larger half-lives are predicted for 4pzH-X derivatives compared to the dimethylated 4pzMe-X derivatives, which can be rationalized by the stabilizing short CH···π interactions in the T-shaped conformation of Z-4pzH-X (Figure 2

• 4pzH-Pyr compounds, the destabilizing nature of the Cl···pyrazole interaction is evidenced by the absence of heteroring tilting in the T-shaped Z-isomers of the 4pzH-X family (θ = 97° and 94° for 4pzH-Cl1 and 4pzH-Cl2), and the systematic decrease in θ for the 4pzMe-X series in going from 4pzMe (138

• highly depends on the molecular conformation, significantly increasing for T-shaped structures (4pzH-X) compared to twisted arrangements (4pzMe-X), and thus leading to larger n–π* band separation for the 4pzH-X series [18]. On the other hand, the intense π–π* transition of the Z-isomer is generally found

Adhesion, forces and the stability of interfaces

• Robin Guttmann,
• Johannes Hoja,
• Christoph Lechner,
• Reinhard J. Maurer and
• Alexander F. Sax

Beilstein J. Org. Chem. 2019, 15, 106–129, doi:10.3762/bjoc.15.12

• series starts with dipoles, whereas in non-polar molecules it starts with quadrupoles or higher multipoles. Accordingly, there will always be electrostatic interactions of different ranges between molecules with static multipoles. For example, the T-shaped equilibrium structure of the benzene dimer is

Metal-free formal synthesis of phenoxazine

• Gabriella Kervefors,
• Antonia Becker,
• Chandan Dey and
• Berit Olofsson

Beilstein J. Org. Chem. 2018, 14, 1491–1497, doi:10.3762/bjoc.14.126

• the neat crude product at rt, along with 52% of 4-iodoanisol (see Supporting Information File 1). This observation is in line with a ligand-coupling (LC) mechanism [30][35][36] where the observed byproduct could be the T-shaped intermediate 9 or the corresponding 4-coordinated species with two

Atom-economical group-transfer reactions with hypervalent iodine compounds

• Andreas Boelke,
• Peter Finkbeiner and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2018, 14, 1263–1280, doi:10.3762/bjoc.14.108

• arylation protocols [18][19][20][21][22]. While in solid state they clearly have a T-shaped pseudotrigonal bipyramid structure, the common structural motif for λ3-iodanes, recent theoretical investigations revealed a potential role of the cationic, normal valent tetrahedral form, in atom transfer processes

Preparation, structure, and reactivity of bicyclic benziodazole: a new hypervalent iodine heterocycle

• Akira Yoshimura,
• Michael T. Shea,
• Cody L. Makitalo,
• Melissa E. Jarvi,
• Gregory T. Rohde,
• Akio Saito,
• Mekhman S. Yusubov and
• Viktor V. Zhdankin

Beilstein J. Org. Chem. 2018, 14, 1016–1020, doi:10.3762/bjoc.14.87

• distorted T-shaped geometry with an N(1)–I(1)–N(2) angle of 153.90 (15)°. Compared to other reported bicyclic hypervalent iodine compounds [23][25][37], this is the most bent structure at the N(1)–I(1)–N(2) angle. An additional relatively weak intermolecular coordination between the iodine atom and the

Synthesis of fluoro-functionalized diaryl-λ³-iodonium salts and their cytotoxicity against human lymphoma U937 cells

• Prajwalita Das,
• Etsuko Tokunaga,
• Hidehiko Akiyama,
• Hiroki Doi,
• Norimichi Saito and
• Norio Shibata

Beilstein J. Org. Chem. 2018, 14, 364–372, doi:10.3762/bjoc.14.24

• SF5-diaryliodonium salts 3p, 4b, 5a and 6a were characterized spectroscopically. The single crystal X-ray structure of 3p was also analysed. The SF5-diaryliodonium salt 3p has a T-shaped geometry at the iodine centre, consistent with the general structure of diaryliodonium salts [33] (Figure 3

Aggregation behaviour of a single-chain, phenylene-modified bolalipid and its miscibility with classical phospholipids

• Simon Drescher,
• Vasil M. Garamus,
• Christopher J. Garvey,
• Annette Meister and
• Alfred Blume

Beilstein J. Org. Chem. 2017, 13, 995–1007, doi:10.3762/bjoc.13.99

• DPPC/DHPC systems [49], or for mixtures of phospholipids with other amphiphilic substances, e.g., in PEG-stabilized bilayer systems [50][51], for phospholipids with membrane scaffold proteins [52][53] or in combination with copolymers [54][55], or for DPPC in mixture with a T-shaped amphiphile [56

Ring-whizzing in polyene-PtL₂ complexes revisited

• Oluwakemi A. Oloba-Whenu,
• Thomas A. Albright and
• Chirine Soubra-Ghaoui

Beilstein J. Org. Chem. 2016, 12, 1410–1420, doi:10.3762/bjoc.12.135

• using the B3LYP hybrid functional and a different basis set. The computed geometric parameters for the molecules are very close to each other. One Pt–C bond is short (2.10 Å) while the other two flanking bonds are 2.52 Å. Thus, 20 strongly resembles an η1 14 electron complex with a “T” shaped geometry

Biosynthesis of α-pyrones

• Till F. Schäberle

Beilstein J. Org. Chem. 2016, 12, 571–588, doi:10.3762/bjoc.12.56

• chain is placed into the proximal cavity, orienting the α-carbon in a position suitable for the nucleophilic attack by the cysteine-tethered, activated chain. Thereby, the second chain is still attached to the ACP, the phosphopantetheine residue reaching into the T-shaped catalytic cavity, enabling the

• -tethered chains are interconnected by the catalytic activity of a free-standing KS. In the second step the lactonization takes place, facilitated by the keto–enol tautomerism. Thereby the α-pyrone 78 is formed. Structures of csypyrones. Schematic drawing of the T-shaped catalytic cavities of the related

• enzymes CorB and MxnB. The two cavities, each harboring one chain are depicted in green and blue, respectively. The phosphopantetheine arm of the ACP reaches into the T-shaped catalytic cavity through a third hydrophobic channel. The oxyanion hole is highlighted by a pink circle. In that way the two

Synthesis of dinucleoside acylphosphonites by phosphonodiamidite chemistry and investigation of phosphorus epimerization

• William H. Hersh

Beilstein J. Org. Chem. 2015, 11, 184–191, doi:10.3762/bjoc.11.19

• contrast, did not yield a trigonal planar transition state, but rather gave a T-shaped transition state. In fact, such a result has been reported for PF3 [59][60] and is due to the presence of the highly electronegative atoms bound to phosphorus. While the alkoxy groups of the phosphite triester are

• calculations were then carried out on the chiral acylphosphonite 21 with the expectation that a high phosphite-like barrier might occur. In fact, the barrier of 41.7 kcal/mol was slightly higher than the phosphite triester calculation. Unlike the phosphite T-shaped transition state, this occurs via a trigonal

Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores

• Clara Orofino-Pena,
• Diego Cortizo-Lacalle,
• Joseph Cameron,
• Muhammad T. Sajjad,
• Pavlos P. Manousiadis,
• Neil J. Findlay,
• Alexander L. Kanibolotsky,
• Dimali Amarasinghe,
• Peter J. Skabara,
• Tell Tuttle,
• Graham A. Turnbull and
• Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2704–2714, doi:10.3762/bjoc.10.285

• -shaped molecules. The other series (T-Bn, n = 1–4) represents star-shaped systems with the arms in the meso- and β-positions, providing T-shaped molecules. Results and Discussion Synthesis For the synthesis of the Y-B1–Y-B4 series a convergent strategy was chosen (Scheme 1). The modified Suzuki coupling

• bathochromically shifted optical transitions compared with their T-shaped analogues. The phenyl linker attached to the meso-position is also more twisted in T-B1 (80.8°) than in Y-B1 (58.0°) because the methyl groups in the 1,7-positions exert greater steric hindrance than the hydrogen substituents of Y-B1. The

Carbenoid-mediated nucleophilic “hydrolysis” of 2-(dichloromethylidene)-1,1,3,3-tetramethylindane with DMSO participation, affording access to one-sidedly overcrowded ketone and bromoalkene descendants^§

• Rudolf Knorr,
• Thomas Menke,
• Johannes Freudenreich and
• Claudio Pires

Beilstein J. Org. Chem. 2014, 10, 307–315, doi:10.3762/bjoc.10.28

• (2.80 g, 11.0 mmol), dimethyl sulfoxide (45 mL), and a magnetic stirring bar were placed in a round-bottomed flask carrying either a wide-bore connection to a cooled trap or a T-shaped glass-tube with a bubbler and gas inlet. This suspension was stirred at 60 °C until 6 was completely dissolved. Freshly

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

True and masked three-coordinate T-shaped platinum(II) intermediates

• Manuel A. Ortuño,
• Salvador Conejero and
• Agustí Lledós

Beilstein J. Org. Chem. 2013, 9, 1352–1382, doi:10.3762/bjoc.9.153

• organometallic transformations. Although very few authenticated three-coordinate Pt(II) complexes have been characterized, a much larger number of complexes can be described as operationally three-coordinate in a kinetic sense. In these compounds, which we have called masked T-shaped complexes, the fourth

• position is occupied by a very weak ligand (agostic bond, solvent molecule or counteranion), which can be easily displaced. This review summarizes the structural features of the true and masked T-shaped Pt(II) complexes reported so far and describes synthetic strategies employed for their formation

• . Moreover, recent experimental and theoretical reports are analyzed, which suggest the involvement of such intermediates in reaction mechanisms, particularly C–H bond-activation processes. Keywords: C–H bond activation; intermediate; platinum(II); reactive intermediates; three-coordinate; T-shaped; Review

Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit

• Govindaswamy Shanker,
• Marko Prehm and
• Carsten Tschierske

Beilstein J. Org. Chem. 2012, 8, 472–485, doi:10.3762/bjoc.8.54

• the segmental motions of the two interconnected mesogenic units, and hence these chains are also assigned as spacers. The properties of these dimesogens strongly depend on the topology of connection [11], the spacer length and spacer parity, resulting in linear and bent [1][3], T-shaped [12][13][14

Koch–Haaf reaction of adamantanols in an acid-tolerant hastelloy-made microreactor

• Takahide Fukuyama,
• Yu Mukai and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2011, 7, 1288–1293, doi:10.3762/bjoc.7.149

• this reactor system, a hastelloy-made microextraction unit (a flow-workup system) was attached (Figure 2 and Figure 3). The microextraction unit has three inlets and one outlet (channel size: 1 mm i.d. × 14 cm). The reaction mixture was mixed at T-shaped junctions with Et2O and water, and a biphasic

Homocoupling of aryl halides in flow: Space integration of lithiation and FeCl₃ promoted homocoupling

• Aiichiro Nagaki,
• Yuki Uesugi,
• Yutaka Tomida and
• Jun-ichi Yoshida

Beilstein J. Org. Chem. 2011, 7, 1064–1069, doi:10.3762/bjoc.7.122

• been effectively accomplished in an integrated flow microreactor system. Results and Discussion First, we focused on the generation of p-methoxyphenyllithium from p-bromoanisole (Scheme 1). A flow microreactor system, consisting of two T-shaped micromixers (M1 and M2) and two microtube reactors (R1 and

• halide followed by reaction with methanol. T-shaped micromixer: M1 (inner diameter: 250 μm), and M2 (inner diameter: 500 μm), microtube reactor: R1 and R2 ( = 1000 μm, length = 50 cm), a solution of aryl halides: 0.10 M in THF (6.0 mL/min), a solution of lithium reagent: 0.40 M or 0.42 M in hexane (n

• with scatter overlay shows the yields of anisole (%), which are indicated by small circles. Integrated flow microreactor system for oxidative homocoupling reaction of aryllithium with FeCl3. T-shaped micromixer: M1 (inner diameter: 250 μm), M2 (inner diameter: 500 μm), and M3 (inner diameter: 500 μm

Continuous flow enantioselective arylation of aldehydes with ArZnEt using triarylboroxins as the ultimate source of aryl groups

• Julien Rolland,
• Xacobe C. Cambeiro,
• Carles Rodríguez-Escrich and
• Miquel A. Pericàs

Beilstein J. Org. Chem. 2009, 5, No. 56, doi:10.3762/bjoc.5.56

• triethylboroxin mixture in toluene). Both flows were mixed in a T-shaped piece placed immediately before the reactor, in order to minimize the amount of background, non-enantioselective addition reaction before contact with the supported catalyst. Additionally, a supply of dry toluene was connected to both pumps

Acid- mediated reactions under microfluidic conditions: A new strategy for practical synthesis of biofunctional natural products

• Katsunori Tanaka and
• Koichi Fukase

Beilstein J. Org. Chem. 2009, 5, No. 40, doi:10.3762/bjoc.5.40

• ). After the reaction mixture was allowed to flow at −78 °C for an additional 47 seconds through a reactor tube (Ø = 1.0 mm, l = 1.0 m), the mixture was quenched by another flow of excess triethylamine dissolved in dichloromethane by using a T-shaped mixer at −78 °C. When the concentrations of the donor 1a

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

• in a controlled manner into the system and was mixed with the toluene solution containing a radical mediator, a radical initiator and a substrate in a T-shaped micromixer (stainless steel, internal diameter: 1000 μm). This biphasic (gas-liquid) mixture was then guided through a stainless steel

• 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

• ), which was then attached to a syringe pump. The system was pressurized with CO (83 atm) by means of the pressure control valve. The flow rate of CO was controlled at 0.14 mL/min by the mass flow controller. The toluene solution was introduced at a flow rate of 0.37 mL/min, then was mixed with CO in the T

Synthesis of unsymmetrically substituted biaryls via sequential lithiation of dibromobiaryls using integrated microflow systems

• Aiichiro Nagaki,
• Naofumi Takabayashi,
• Yutaka Tomida and
• Jun-ichi Yoshida

Beilstein J. Org. Chem. 2009, 5, No. 16, doi:10.3762/bjoc.5.16

• of two T-shaped micromixers (M1 and M2) and two microtube reactors (R1 and R2) shown in Figure 1. A solution of 2,2′-dibromobiphenyl (1) (0.10 M) in THF (flow rate: 6.00 ml·min−1, 0.60 mmol min−1) and a solution of n-BuLi (0.50 M) in hexane (flow rate: 1.20 ml·min−1, 0.60 mmol min−1) were introduced

• monolithiation of 2,2′-dibromobiphenyl (1) followed by the reaction with an electrophile using the microflow system in hand, sequential introduction of two electrophiles (E1 and E2) onto 2,2′-dibromobiphenyl (1) was examined using an integrated microflow system composed of four T-shaped micromixers (M1, M2, M3

• and M4) and four microtube reactors (R1, R2, R3 and R4) shown in Figure 3. In this case, T-shaped micromixers M3 and M4 having the inside diameter of 500 μm were used to suppress the pressure increase because an increase in the numbers of micromixers and microtube reactors in the system causes a