110-69-0Relevant academic research and scientific papers
A green chemical approach for the N-alkylation of aldoximes to form nitrones in organized aqueous media and their in situ cycloaddition with olefins
Hota, Sandip K.,Chatterjee, Amrita,Bhattacharya, Pranab K.,Chattopadhyay, Partha
, p. 169 - 176 (2009)
Aldoximes react with α,β-unsaturated carbonyl and sulfonyl compounds in organized aqueous media (nanoreactor system) using dodecylbenzenesulfonic acid (DBSA) as surfactant to generate N-alkylated nitrones, which undergo intermolecular cycloaddition in the same pot with maleimides to give the desired cycloadduct in absence of any organic solvent and catalyst. Divinyl sulfone was successfully used for both N-alkylation and intramolecular cycloaddition, affording only one cycloadduct. This is a new example of green chemistry and provides a new aspect of reactions in water.
7-Oxa-4-thia-1-aza-bicyclo[3.2.1]octane 4,4-Dioxides: Mechanochemical Synthesis by Tandem Michael Addition–1,3-Dipolar Cycloaddition of Aldoximes and Evaluation of Antibacterial Activities
Bhutia, Zigmee T.,Das, Avijit,Biswas, Malabika,Chatterjee, Amrita,Banerjee, Mainak
, p. 506 - 514 (2018)
A solvent-free, green, and efficient mechanochemical method for the synthesis of a series of bridged bicyclo aza-sulfone derivatives, namely 7-oxa-4-thia-1-aza-bicyclo[3.2.1]octane 4,4-dioxides through tandem Michael addition–1,3-dipolar cycloaddition of aldoximes was developed. Mechanochemical grinding/milling facilitates quick formation of aldoximes from corresponding aldehydes and hydroxylamine, which upon reaction with divinyl sulfone in a mixer mill affords 7-oxa-4-thia-1-aza-bicyclo[3.2.1]octane 4,4-dioxide derivatives in good overall yields. The newly synthesized bicyclo aza-sulfone derivatives 4 were screened for antibacterial activities. Mostly bicyclo aza-sulfones derived from electron-rich aromatic aldehydes inhibit the growth of Mycobacterium smegmatis (mc2155) and those from aliphatic aldehydes the growth of Escherichia coli (DH5α) in moderate to good effect. However, butyraldehyde-derived compound 4r was very effective against both M. smegmatis and E. coli. The key advantages of this mechanochemical method are catalyst- and solvent-free conditions, shorter reaction time, and formation of a new series of 7-oxa-4-thia-1-aza-bicyclo[3.2.1]octane 4,4-dioxide derivatives, which are good antibacterial agents against M. smegmatis and E. coli.
Site-specific catalytic activities to facilitate solvent-free aerobic oxidation of cyclohexylamine to cyclohexanone oxime over highly efficient Nb-modified SBA-15 catalysts
Ding, Wei,Mao, Liqiu,Peng, Haoyu,Yin, Dulin,Zhong, Wenzhou
, p. 3409 - 3422 (2020/06/09)
The development of highly active and selective heterogeneous catalysts for efficient oxidation of cyclohexylamine to cyclohexanone oxime is a challenge associated with the highly sensitive nitrogen center of cyclohexylamine. In this work, dispersed Nb oxide supported on SBA-15 catalysts are disclosed to efficiently catalyze the selective oxidation of cyclohexylamine with high conversion (>75%) and selectivity (>84%) to cyclohexanone oxime by O2without any addition of solvent (TOF = 469.8 h?1, based on the molar amount of Nb sites). The role of the active-site structure identity in dictating the site-specific catalytic activities is probed with the help of different reaction and control conditions and multiple spectroscopy methods. Complementary to the experimental results, further poisoning tests (with KSCN or dehydroxylation reagents) and DFT computational studies clearly unveil that the surface exposed active centers toward activation of the reactants are quite different: the surface -OH groups can catch the NH2group from cyclohexylamine by forming a hydrogen bond and lead to a more facile cyclohexylamine oxidation to desired products, while the monomeric or oligomeric Nb sites with a highly distorted structure play a key role in the dissociation of O2molecules beneficial for insertion of active oxygen species into cyclohexylamine. These catalysts exhibit not only satisfactory recyclability for cyclohexylamine oxidation but also efficiently catalyze the aerobic oxidation of a wide range of amines under solvent-free conditions.
Efficient synthesis of 1,2,4-oxadiazine-5-ones via [3+3] cycloaddition of in situ generated aza-oxyallylic cations with nitrile oxides
Wang, Gangqiang,Chen, Rongxing,Zhao, Sen,Yang, Liangfeng,Guo, Haibing,Sun, Shaofa,Wang, Jian,Domena, Justin,Xing, Yalan
supporting information, p. 2018 - 2020 (2018/04/25)
1,2,4-Oxadiazin-5-ones were prepared via [3+3] cycloaddition of in situ generated aza-oxyallylic cations with nitrile oxides in good yields and excellent functional group compatibility. This efficient transformation is metal-free and is promoted by an inorganic base Cs2CO3. In addition, this reaction features simple-operation, mild conditions, and high regioselectivity.
An Efficient One–pot Procedure for the Direct Preparation of 4,5-Dihydroisoxazoles from Amides
Slagbrand, Tove,Kervefors, Gabriella,Tinnis, Fredrik,Adolfsson, Hans
supporting information, p. 1990 - 1995 (2017/06/09)
A Mo(CO)6 (molybdenumhexacarbonyl) catalyzed reductive functionalization of amides to afford 5-amino substituted 4,5-dihydroisoxazoles is presented. The reduction of amides generates reactive enamines, which upon the addition of hydroximinoyl chlorides and base undergoes a 1,3-dipolar cycloaddition reaction that gives access to the desired heterocyclic compounds. The transformation of amides is highly chemoselective and tolerates functional groups such as nitro, nitriles, esters, and ketones. Furthermore, a versatile scope of 4,5-dihydroisoxazoles derived from a variety of hydroximinoyl chlorides and amides is demonstrated. (Figure presented.).
Iron-catalyzed synthesis of benzoxazoles by oxidative coupling/cyclization of phenol derivatives with benzoyl aldehyde oximes
Gao, Sen,Gao, Liming,Meng, Hong,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 9886 - 9889 (2017/09/11)
An iron-catalyzed oxidative coupling/cyclization reaction for the synthesis of benzoxazoles at room temperature is reported. This reaction was enabled by an inexpensive iron(iii) catalyst by treating readily available phenol derivatives with benzoyl aldehyde oximes. Mechanistic studies show that benzoyl aldehyde oxime is not only used as a substrate, but also serves as an ancillary ligand to support the iron salt in the promotion of the transformation.
Water-Assisted Nitrile Oxide Cycloadditions: Synthesis of Isoxazoles and Stereoselective Syntheses of Isoxazolines and 1,2,4-Oxadiazoles
Kesornpun, Chatchai,Aree, Thammarat,Mahidol, Chulabhorn,Ruchirawat, Somsak,Kittakoop, Prasat
supporting information, p. 3997 - 4001 (2016/03/19)
Conventional methods generate nitrile oxides from oxime halides in organic solvents under basic conditions. However, the present work revealed that water-assisted generation of nitrile oxides proceeds under mild acidic conditions (pH 4-5). Cycloadditions of nitrile oxides with alkynes and alkenes easily occurred in water without using catalysts, thus yielding isoxazoles and isoxazolines, respectively, with excellent stereoselectivity toward five- and six-membered cyclic alkenes. A double stereoselective cycloaddition of two units of a nitrile oxide with cyclohexene was also achieved, thus yielding 1,2,4-oxadiazole derivatives having a unique hybrid isoxazoline-oxadiazole skeleton. Enantiomerically pure isoxazolines were prepared from monoterpenes with a ring strain. In one case, the isoxazoline with a butterfly-like structure was simply prepared, and it might be used as a ligand in asymmetric catalysis.
M-CPBA mediated metal free, rapid oxidation of aliphatic amines to oximes
Patil, Vilas V.,Gayakwad, Eknath M.,Shankarling, Ganapati S.
, p. 781 - 786 (2016/02/18)
An efficient, rapid oxidation of various aliphatic amines to oximes using m-CPBA as an oxidant in ethyl acetate is described. High conversion (100%) with >90% oxime selectivity is achieved at room temperature under catalyst-free conditions. Mild reaction conditions along with an easy work up procedure offer lower byproduct formation and high selectivity for oximes in good yield and purity.
Highly efficient and stable peracid for rapid and selective oxidation of aliphatic amines to oximes
Patil, Vilas V.,Gayakwad, Eknath M.,Shankarling, Ganapati S.
, p. 6677 - 6682 (2015/08/06)
A novel, transition-metal free, rapid approach for selective oxidation of aliphatic and benzylic amines to oximes is described. The dodecanebis(peroxoic acid)-DMF combination efficiently oxidizes various aliphatic amines at 50 °C temperature to give 100% conversion in 20 min with high oxime selectivity. The peroxy acid used here shows exceptional stability at room temperature and is non-shock sensitive in nature, which was confirmed by differential scanning colorimetric (DSC) analysis.
Rhodium(II)-Catalyzed Formal [3 + 2] Cycloaddition of N-Sulfonyl-1,2,3-triazoles with Isoxazoles: Entry to Polysubstituted 3-Aminopyrroles
Lei, Xiaoqiang,Li, Longbo,He, Yu-Peng,Tang, Yefeng
supporting information, p. 5224 - 5227 (2015/11/18)
A novel rhodium(II)-catalyzed formal [3 + 2] cycloaddition of N-sulfonyl-1,2,3-triazoles with isoxazoles has been achieved that provides an efficient method for the synthesis of polysubstituted 3-aminopyrrole derivatives. An operationally simple one-pot synthesis of the titled compounds from terminal alkynes, tosyl azide, and isoxazoles was also developed. The presented reaction affords an illustrative example of employing 1,2,3-triazoles as the [2C]-component in relevant cycloaddition reactions.
