6165-69-1Relevant articles and documents
Thiophene-derivatized Pybox and its highly luminescent lanthanide ion complexes
De Bettencourt-Dias, Ana,Viswanathan, Subha,Rollett, Alexandra
, p. 15436 - 15437 (2007)
A new complex of 4-thiophen-3-yl-pyridine-2,6-bis(oxazoline) with Eu(III) triflate has been isolated. This complex and its Tb(III) analogue are luminescent in the solid state. The complexes dissolve with partial retention of the solid-state structure in acetonitrile to yield highly luminescent solutions with quantum yields of 76.2 and 58.6% for red and green emission, respectively. Copyright
Synthesis and utility of 3-silylthiophenes having perfluoroalkyl groups
Honda, Mitsunori,Taniguchi, Yusuke,Hayashi, Tomohiro,Kunimoto, Ko-Ki,Segi, Masahito,Yamaguchi, Takahiro
, p. 4554 - 4558 (2017)
The synthesis of a novel class of 3-silyl substituted thiophenes possessing perfluoroalkyl groups on the silicon atom was investigated. The treatment of 3-bromothiophene with n-butyllithium followed by the reaction with halosilanes proceeded to afford the corresponding 3-silyl substituted thiophenes 1 in good yields. The chemical polymerization of the resulting 1 did not work well. However, the electropolymerization of 3-silylthiophenes 1a and 1b provided the corresponding polymers 5a and 5b with head-to-tail regioregularity. The cyclic voltammogram of the resulting polymers 5a and 5b indicated both n- and p-doping properties.
Transition-Metal-Free Borylation of Aryl Bromide Using a Simple Diboron Source
Han, Min Su,Lim, Taeho,Ryoo, Jeong Yup
, p. 10966 - 10972 (2020/09/23)
In this study, we developed a simple transition-metal-free borylation reaction of aryl bromides. Bis-boronic acid (BBA), was used, and the borylation reaction was performed using a simple procedure at a mild temperature. Under mild conditions, aryl bromides were converted to arylboronic acids directly without any deprotection steps and purified by conversion to trifluoroborate salts. The functional group tolerance was considerably high. The mechanism study suggested that this borylation reaction proceeds via a radical pathway.
Copper-Catalyzed Monoorganylation of Trialkyl Borates with Functionalized Organozinc Pivalates
Fu, Ying,Gou, Bei-Lei,Shi, Chun-Zhao,Du, Zhengyin,Shen, Tong
, p. 4253 - 4257 (2018/09/18)
Organozinc pivalates, a recently developed air- and moisture-stable organozinc species, were found for the first time as excellent organometallic species in the monoorganylation of trialkyl borates whereby boronic acids were prepared in high yields. The significant advantage of organozinc pivalates over another previously employed organometallic reagents, e. g., organolithium reagents, Grignard reagents and organozinc halides, is that the generation of multiorganylation byproducts such as borinic acids and trialkylboranes were completely suppressed. Additionally, the in situ generated boronates could be directly arranged into Suzuki-Miyaura type cross-coupling reactions to produce biaryls in high yields.
An efficient method for the hydrolysis of potassium organotrifluoroborates promoted by montmorillonite K10
Silva, Renato L.,Santos, Cosme S.,Santos, Jonh A. M.,Oliveira, Roberta A.,Menezes, Paulo H.,Freitas, Juliano C. R.
, p. 1777 - 1785 (2018/09/04)
An efficient and non-expensive method for conversion of diverse potassium organotrifluoroborates to their corresponding boronic acids promoted by montmorillonite K10 using water as the reaction solvent is described. Further interconversion of potassium organotrifluoroborates to their corresponding boronic esters, via boronic acid intermediates was also successfully accomplished. The products were obtained in good yields, being the rate of hydrolysis influenced by the type of substituent present in the boronic acid.
Development of a Concise Multikilogram Synthesis of LPA-1 Antagonist BMS-986020 via a Tandem Borylation-Suzuki Procedure
Smith, Michael J.,Lawler, Michael J.,Kopp, Nathaniel,McLeod, Douglas D.,Davulcu, Akin H.,Lin, Dong,Katipally, Kishta,Sfouggatakis, Chris
, p. 1859 - 1863 (2017/11/24)
The process development for the synthesis of BMS-986020 (1) via a palladium catalyzed tandem borylation/Suzuki reaction is described. Evaluation of conditions culminated in an efficient borylation procedure using tetrahydroxydiboron followed by a tandem Suzuki reaction employing the same commercially available palladium catalyst for both steps. This methodology addressed shortcomings of early synthetic routes and was ultimately used for the multikilogram scale synthesis of the active pharmaceutical ingredient 1. Further evaluation of the borylation reaction showed useful reactivity with a range of substituted aryl bromides and iodides as coupling partners. These findings represent a practical, efficient, mild, and scalable method for borylation.
Covalent functionalization of graphene with polythiophene through a Suzuki coupling reaction
Yao, Yanjin,Gao, Jie,Bao, Feng,Jiang, Sanfeng,Zhang, Xu,Ma, Rui
, p. 42754 - 42761 (2015/05/27)
In our tentative previous work, graphene was covalently functionalized by hexylbenzene and poly(9,9-dihexylfluorene) (PF) through a Suzuki coupling reaction. In this paper, thiophene and polythiophene (PTH) were grafted to brominated graphene (Br-Gra) in the same polymeric method. The obtained conjugated system of modified graphene was characterized by various techniques, including Fourier transform-infrared (FT-IR), ultraviolet-vis (UV-vis), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), fluorescence emission spectra, 1H-NMR spectra, and Raman spectroscopy. All the results revealed that thiophene and PTH were successfully grafted to the graphene. What's more, a colour change of their solution (Br-Gra doesn't dissolve in THF, while both thiophene grafted graphene (Gra-3TH) and PTH grafted graphene (Gra-PT) dissolve in THF, and exhibit a black and green color in THF respectively), which is caused by an electron-energy transfer between graphene and the conjugated polymer was also observed. These polymeric conjugated systems of modified graphene materials may open an interesting field for the application of graphene in photoelectric devices.
Vaulted biaryls in catalysis: A structure-activity relationship guided tour of the immanent domain of the VANOL ligand
Guan, Yong,Ding, Zhensheng,Wulff, William D.
supporting information, p. 15565 - 15571 (2013/11/19)
The active site in the BOROX catalyst is a chiral polyborate anion (boroxinate) that is assembled in situ from three equivalents of B(OPh) 3 and one of the VANOL ligand by a molecule of substrate. The substrates are bound to the boroxinate by Hbonds to oxygen atoms O1-O3. The effects of introducing substituents at each position of the naphthalene core of the VANOL ligand are systematically investigated in an aziridination reaction. Substituents in the 4,4′- and 8,8′-positions have a negative effect on catalyst performance, whereas, substituents in the 7- and 7′-positions have the biggest impact in a positive direction. VANOL destination: The active site in the BOROX catalyst is a chiral polyborate anion (boroxinate; see figure) that is assembled in situ from three equivalents of B(OPh)3 and one of the VANOL ligand by a molecule of substrate. The effects of introducing substituents at each position of the naphthalene core of the VANOL ligand are systematically investigated in an aziridination reaction. Copyright
Nickel-catalyzed borylation of halides and pseudohalides with tetrahydroxydiboron [B2(OH)4]
Molander, Gary A.,Cavalcanti, Livia N.,Garcia-Garcia, Carolina
, p. 6427 - 6439 (2013/07/26)
Arylboronic acids are gaining increased importance as reagents and target structures in a variety of useful applications. Recently, the palladium-catalyzed synthesis of arylboronic acids employing the atom-economical tetrahydroxydiboron (BBA) reagent has been reported. The high cost associated with palladium, combined with several limitations of both palladium- and copper-catalyzed processes, prompted us to develop an alternative method. Thus, the nickel-catalyzed borylation of aryl and heteroaryl halides and pseudohalides using tetrahydroxydiboron (BBA) has been formulated. The reaction proved to be widely functional group tolerant and applicable to a number of heterocyclic systems. To the best of our knowledge, the examples presented here represent the only effective Ni-catalyzed Miyaura borylations conducted at room temperature.
On the directing effect of boronate groups in the lithiation of boronated thiophenes
Borowska, Elena,Durka, Krzysztof,Lulinski, Sergiusz,Serwatowski, Janusz,Wozniak, Krzysztof
scheme or table, p. 2208 - 2218 (2012/06/01)
An investigation of thiophene boronates has revealed the usefulness of a metalation reaction in the synthesis of various lithiated thiophene boronates, which were further converted to functionalized thiopheneboronic derivatives. The lithiation of 2- and 3-thienylboronic N-butyldiethanolamine (BDEA) esters with lithium diisopropylamide and lithium 2,2,6,6-tetramethylpiperidide showed that both boronated thiophenes were readily deprotonated. In the latter case, lithiation at the 2-position adjacent both to sulfur and the borocanyl group is thermodynamically favoured due to the significant stabilizing effect of the borocanyl group. Further derivatization with a range of electrophiles followed by hydrolysis afforded various 2-substituted 3-thiopheneboronic acids. Lithiation of the corresponding thiopheneboronic "ate" complexes of the type [ThB(OR)3]Li revealed that the 2-thienyl derivatives could not be effectively deprotonated, whereas the "ate" complex, [3-ThB(OEt)3]Li, was selectively lithiated with nBuLi at C-2. This points to a directing effect of the anionic boronate moiety. The resulting bimetallic species, [(2-Li-3-Th)B(OEt)3]Li, underwent ring-closing dimerization upon heating to give, after subsequent hydrolysis, 4,8-dihydro-4,8-dihydroxy-p-diborino[2,3-b:5,6-b′]dithiophene - a cyclic diborinic acid. A computational study of the lithiation of boronated thiophenes and furans proved that boronation decreases ring-proton acidity. This effect is much stronger for the boronic "ate" complexes than for the corresponding neutral BDEA esters. Calculations of the transition states have shown that the specific directing effect of boronate groups in 3-thienyl derivatives is due to intramolecular oxygen-lithium coordination.
