26818-08-6Relevant articles and documents
Practical two-step synthesis of an enantiopure aliphatic terminal (S)-epoxide based on reduction of haloalkanones with "designer cells"
Berkessel, Albrecht,Rollmann, Claudia,Chamouleau, Francoise,Labs, Stefanie,May, Oliver,Groeger, Harald
, p. 2697 - 2704 (2007)
A practical biocatalytic method for the synthesis of aliphatic β-halogenated (S)-alcohols as epoxide precursors by means of an enantioselective reduction of the corresponding ketones with recombinant whole cells, bearing an alcohol dehydrogenase and a glucose dehydrogenase, was developed. The biotransformations operate at high substrate concentrations of up to 208 g/L, and afford the (S)-β-halohydrins with both high conversions of >95% and enantioselectivities of >99% ee. Base-induced cyclization of the β-halohydrin intermediates gave the desired (S)-epoxides in high yield and enantiomeric purity (>99% ee).
Thiophene-bithiazole based metal-free dye as DSSC sensitizer: Effect of co-adsorbents on photovoltaic efficiency
Panicker, Jayanthy S.,Balan, Bijitha,Soman, Suraj,Ghosh, Tanwistha,Nair, Vijayakumar C.
, p. 101 - 110 (2016)
A new molecule consisting of a bithiazole chromophore sandwiched between two thiophenes, functionalized with benzothiophene unit at one end and cyanoacrylic acid at the other end (BT1) was synthesized, photophysical properties were studied and employed as a photosensitizer in dye-sensitized solar cells (DSSCs). The molecule exhibited an intense absorption in the UV-visible region with absorption extending up to 500 nm. The ground and excited state potentials of BT1 were calculated to be 1.29 and -0.65 V, respectively vs. NHE using cyclic voltammetry. The ground state energy level is more positive than the triiodide electrolyte and excited state energy level is considerably more negative than the TiO2 satisfying the energetic requirements for a photosensitizer in DSSC. The solar cells fabricated from BT1 exhibited an efficiency of 1.13%. The effect of various co-adsorbents (CDCA,TP1 andTP2) on the DSSC performance was investigated in detail. In the presence of CDCA, the photovoltaic efficiency was enhanced to 1.25%, whereas, in the presence of TP1 and TP2, the efficiency lowered to 0.20% and 0.59%, respectively. The increased efficiency in the presence of CDCA could be attributed to the prevention of the aggregation of dye molecules induced by CDCA. On the other hand, TP1 and TP2 were found to be not as effective as CDCA to prevent aggregation leading to the lowering of photoconversion efficiency. [Figure not available: see fulltext.]
CS-symmetric triarylborane substituted bisthiazole for selective detection of F?and CN?ions
Maragani, Ramesh,Reddy, T. Sheshashena,Misra, Rajneesh
, p. 3853 - 3857 (2016)
Triarylborane substituted bisthiazole 1 was designed and synthesized by the Sonogashira cross-coupling reaction for selective detection of F?and CN?ions in the presence of Cl?, Br?, I?and NO2?anions. The detection limits for F?and CN?were found to be 5.7?×?10?6?M and 2.1?×?10?6?M, respectively. The time dependent density functional theory (TD-DFT) calculation at B3LYP on the bisthiazole triarylborane 1 was studied for F?and CN?ions. In the case of 1 Boron is electron deficient, the addition of F?ion should increase the electron density on Boron which was confirmed by electrostatic potential surfaces of bisthiazole triarylborane dyad 1, 1-F.
C2-Symmetric ferrocenyl bisthiazoles: Synthesis, photophysical, electrochemical and DFT studies
Maragani, Ramesh,Gautam, Prabhat,Mobin, Shaikh M.,Misra, Rajneesh
, p. 4802 - 4809 (2016)
A series of donor-acceptor ferrocenyl substituted bisthiazoles 3-8 were designed and synthesized by the Pd-catalyzed Suzuki, Heck, and Sonogashira cross-coupling reactions. Their photophysical, electrochemical and computational studies reveal strong donor-acceptor interactions. The photonic and electrochemical studies show that the ferrocenyl bisthiazoles with vinyl linkage ferrocenyl-bisthiazole 4, show better electronic communication compared to rest of the ferrocenyl bisthiazoles. The time dependent density functional theory (TD-DFT) calculation at B3LYP on the ferrocenyl substituted bisthiazoles 3-5 was performed, in which the ferrocenyl-bisthiazole 4 shows strong donor-acceptor interactions compared to the Fc-bisthiazoles 3 and 5. The thermal stability of the ferrocenyl substituted bisthiazoles 3-8 is reported, in which Fc-bisthiazole 8 shows high thermal stability. The single crystal structures of ferrocenyl-bisthiazoles 3 and 5 are reported.
Visible-light induced metal-free cascade Wittig/hydroalkylation reactions
Miao, Pannan,Li, Ruining,Lin, Xianfeng,Rao, Liangming,Sun, Zhankui
supporting information, p. 1638 - 1641 (2021/03/09)
Cascade reactions are green and powerful transformations for building multiple carbon-carbon bonds in one step. Through a relay olefination and radical addition process, we were able to develop the cascade Wittig/hydroalkylation reactions induced by visible light. This metal-free radical approach features mild conditions, robustness, and excellent functionality compatibility. It allows access to saturated C3 homologation products directly from aldehydes or ketones. The synthetic utility of this method is demonstrated by a two-step synthesis ofindolizidine 209D.
A radical exchange process: Synthesis of bicyclo[1.1.1]pentane derivatives of xanthates
Rout, Saroj Kumar,Marghem, Gilles,Lan, Junjie,Leyssens, Tom,Riant, Olivier
supporting information, p. 14976 - 14979 (2019/12/24)
Bicyclo[1.1.1]pentane (BCP) replacement as a bioisostere in drug molecules has an influence on their permeability, aqueous solubility and in vitro metabolic stability. Thus, the chemical installation of the BCP unit into a chemical entity remains a significant challenge from a synthetic point of view. Here, we have presented a new approach for the installation of the BCP unit on the xanthate moiety by means of a radical exchange process.
An efficient heterogeneous gold(I)-catalyzed hydration of haloalkynes leading to α-halomethyl ketones
Hu, Sifan,Liu, Dayi,Yan, Chenyu,Cai, Mingzhong
supporting information, p. 2983 - 2991 (2018/12/04)
A highly efficient heterogeneous gold(I)-catalyzed hydration of haloalkynes has been developed that proceeds smoothly under mild and neutral conditions and provides a general and practical route for the synthesis of a variety of α-halomethyl ketones with high atom-economy, excellent yield, and recyclability of the gold(I) catalyst. The presented method delivers an attractive alternative to classical α-halogenation of ketones.
1,3-Dibromo-5,5-dimethylhydantoin mediated oxidative amidation of terminal alkenes in water
Ma, Chunhua,Fan, Guojie,Wu, Ping,Li, Zhi,Zhou, Yang,Ding, Qingjie,Zhang, Wei
, p. 9889 - 9894 (2017/12/12)
A variety of terminal alkenes were converted to the corresponding amides in yields of 25 to 86% in water via treatment with 1,3-dibromo-5,5-dimethylhydantoin, followed by reaction with molecular iodine and aq. NH3 (or amine) in one pot. This metal- and organic solvent-free protocol is not only suitable for styrene derivatives, but also, for the first time, works well on terminal aliphatic alkenes.
A new and versatile one-pot strategy to synthesize alpha-bromoketones from secondary alcohols using ammonium bromide and oxone
Rammurthy, Banothu,Swamy, Peraka,Naresh, Mameda,Srujana, Kodumuri,Durgaiah, Chevella,Krishna Sai, Gajula,Narender, Nama
, p. 3710 - 3714 (2017/07/12)
A new, efficient and green protocol for the one-pot synthesis of α-bromoketones from secondary alcohols using cheap, air stable and non-toxic reagents such as NH4Br and oxone has been developed. This reaction proceeds via two consecutive steps such as oxidation of secondary alcohols and oxidative bromination of in situ generated ketones.
Catalytic dehydrogenative dual functionalization of ethers: Dealkylation-oxidation-bromination accompanied by C-O bond cleavage: Via aerobic oxidation of bromide
Moriyama, Katsuhiko,Hamada, Tsukasa,Nakamura, Yu,Togo, Hideo
supporting information, p. 6565 - 6568 (2017/07/10)
Catalytic dehydrogenative dual functionalization (DDF) of ethers via oxidation, dealkylation, and α-bromination by the aerobic oxidation of bromide was developed to obtain the corresponding α-bromo ketones in high yields. In particular, the reaction of substituted tetrahydrofurans as cyclic ethers provided 3,3-dibromo tetrahydrofuran-2-ols in high yields selectively through the double α-bromination.
