70450-40-7Relevant academic research and scientific papers
Iminophosphorane-mediated regioselective umpolung alkylation reaction of α-iminoesters
Kukita, Mayu,Mino, Takashi,Omori, Kazuki,Sakamoto, Masami,Yoshida, Yasushi
, p. 4551 - 4564 (2021/05/31)
Umpolung reactions of imines, especially the asymmetric reactions, have been extensively studied as they provide access to important chiral amines in an efficient manner. The reactions studied range from simple Michael reactions to several kinds of other reactions such as the aza-benzoin reaction, aza-Stetter reaction, addition with MBH carbonate, and Ir-catalysed allylation. Herein, we report the first umpolung alkylation reaction of α-iminoesters with alkyl halides mediated by iminophosphorane as an organic superbase. The desired products were obtained in up to 82% yield with almost perfect regioselectivities. The key to the regioselectivity of this reaction was the use of 4-trifluoromethyl benzyl imines as a substrate. The products were successfully derivatised into the more functionalised molecules in good yields.
Continuous Flow Preparation of (Hetero)benzylic Lithiums via Iodine-Lithium Exchange Reaction under Barbier Conditions
Weidmann, Niels,Harenberg, Johannes H.,Knochel, Paul
supporting information, p. 5895 - 5899 (2020/08/12)
Herein we report the generation of benzylic lithiums via an iodine-lithium exchange reaction on benzylic iodides performed in continuous flow using tBuLi as the exchange reagent. The resulting benzylic lithium species are trapped in situ by carbonyl electrophiles under Barbier conditions, resulting in benzylic secondary and tertiary alcohols. This flow procedure further allows the generation of highly reactive heterobenzylic lithium compounds, which are difficult to generate under batch conditions. A general scale-up was possible without further optimization.
Preparation method of benzyl iodide and derivatives thereof
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Paragraph 0071-0075, (2020/06/09)
The invention discloses a preparation method of benzyl iodide and derivatives thereof. The preparation method comprises the following steps: under the reduction action of sodium borohydride, a benzylalcohol compound shown as a formula I reacts with elemental iodine to obtain benzyl iodide shown as a formula II and derivatives thereof; in the formula I and the formula II, R represents one or moresubstituents on a benzene ring and is selected from at least one of aryl, substituted or unsubstituted alkyl, halogen and nitro. The preparation method of benzyl iodide and derivatives thereof is scientific and reasonable, sodium borohydride which is mild in reactivity, low in price and easily available is used as a reducing agent, and elemental iodine is convenient and easily available; in addition, the preparation method has the characteristics of simplicity and convenience in operation, high synthesis yield, easiness in product purification, environmental friendliness and the like.
A new HPLC-UV derivatization approach for the determination of potential genotoxic benzyl halides in drug substances
Ji, Shunli,Gao, Hongbin,Xia, Xingya,Zheng, Feng
, p. 25797 - 25804 (2019/08/28)
Benzyl halides, widely used as alkylation reagents in drug synthesis, are potential genotoxic impurities (PGTIs) required to be controlled at trace levels. However, the existing analytical methods for benzyl halides often suffer from matrix interferences or low derivatization efficiency of benzyl chlorides. In this paper, a simple derivatization HPLC-UV method was developed for the analysis of these residual trace benzyl halides in drug substances. 1-(4-Nitrophenyl) piperazine (4-NPP) was selected as a new derivatization reagent because it shifted well the benzyl halides derivatives away to the near visible range (392 nm), which could minimize the matrix interferences from the drug substances and related impurities. Meanwhile, potassium iodide (KI) was used to convert the mixed benzyl halides into benzyl iodides before derivatization. The derivatization parameters were also optimized using the design of experiments (DoE) for achieving the best reaction efficiency. The results showed that the new approach had high specificity and sensitivity, and the LOQs were 7-9 μg g-1 relative to 5 mg mL-1 antipyrine and 17.5-22.5 μg g-1 relative to 2 mg mL-1 oroxylin A. The method is a valuable alternative for the determination of residual benzyl halides in the drug substances.
Preparation method of epoxiconazole
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Paragraph 0057; 0065; 0066; 0075; 0084, (2018/07/07)
The invention relates to a preparation method of epoxiconazole. The preparation method comprises the following steps: in the presence of an inert solvent, enabling fluoroacetophenone and a brominationreagent to react at -10 DEG C to 50 DEG C; carrying out
Rhodium-Catalyzed Generation of Anhydrous Hydrogen Iodide: An Effective Method for the Preparation of Iodoalkanes
Zeng, Chaoyuan,Shen, Guoli,Yang, Fan,Chen, Jingchao,Zhang, Xuexin,Gu, Cuiping,Zhou, Yongyun,Fan, Baomin
supporting information, p. 6859 - 6862 (2018/10/25)
The preparation of anhydrous hydrogen iodide directly from molecular hydrogen and iodine using a rhodium catalyst is reported for the first time. The anhydrous hydrogen iodide generated was proven to be highly active in the transformations of alkenes, phenyl aldehydes, alcohols, and cyclic ethers to the corresponding iodoalkanes. Therefore, the present methodology not only has provided convenient access to anhydrous hydrogen iodide but also offers a practical preparation method for various iodoalkanes in excellent atom economy.
A mild and highly chemoselective iodination of alcohol using polymer supported DMAP
Das, Diparjun,H Anal, Jasha Momo,Rokhum, Lalthazuala
, p. 1695 - 1701 (2017/03/08)
The synthesis of organic compounds using polymer supported catalysts and reagents, where the required product is always in solution, has been of great interest in recent years, both in industries and academia especially in pharmaceutical research. Here, a simple and efficient method for conversion of alcohols into their iodides in high yield using polymer supported 4-(Dimethylamino)pyridine (DMAP) is described. Polymer supported DMAP is used in catalytic amount and is recovered and reused several times. Additionally, this method is highly chemoselective. [Figure not available: see fulltext.]
An efficient and selective method for the iodination and bromination of alcohols under mild conditions
Khazdooz, Leila,Zarei, Amin,Aghaei, Hamidreza,Azizi, Ghobad,Gheisari, Mohammad Mehdi
, p. 168 - 171 (2015/12/30)
A straightforward and effective procedure for the conversion of a variety of alcohols into the corresponding alkyl iodides and bromides is described using KX/P2O5 (X = I, Br). The reactions were easily carried out in acetonitrile under mild conditions. Using this method, the selective conversion of benzylic alcohols in the presence of aliphatic alcohols was achieved.
Uranyl Schiff base complexes as new heterogeneous catalysts for halogen exchange reactions between alkyl halides and elemental halogens
Naeimi,Nazifi
, p. 1814 - 1818 (2016/05/11)
Mild and effective procedure for the halogen exchange reaction of alkyl halides with elemental iodine and bromine catalyzed with uranyl Schiff base complexes in various aprotic solvents was developed. Corresponding alkyl bromides and iodides were obtained with high yields within 20—70 min. The structures of the target products were confirmed by physical and spectroscopic data.
Ionic liquid-induced conversion of methoxymethyl-protected alcohols into nitriles and iodides using [Hmim][NO3]
Noei, Jalil,Mirjafari, Arsalan
supporting information, p. 4424 - 4426 (2014/08/05)
This Letter reports a one-pot efficient conversion of methoxymethyl-ethers into their corresponding nitriles and iodides using the ionic liquid, 1-methyl-3H-imidazolium nitrate ([Hmim][NO3]) under microwave irradiation. A variety of products were prepared in high yields using this method.
