- Preparation method of chiral 2 - aminomethyltetrahydrofuran (by machine translation)
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The invention provides a preparation method of chiral 2 -aminomethyl tetrahydrofuran, which comprises the following steps: (1) reaction of chiral epichlorohydrin with 2 - chloroethyl magnesium bromide to generate chiral 1-chloro 5 -pentanol; (-2 -) chiral 2-benzamido 1-chloro 5 - pentanol to react under the action of a palladium catalyst to generate chiral -2 -benzamidomethyl tetrahydrofurane in the presence of a basic substance to form chiral 5 - 1 - dichloro -5 -1-pentanol and a 4 chiral 2 -2 - 1 -dichloro 3 pentanol in -2 - the presence of a basic substance to form -5 - an intramolecular ring-closing reaction in the presence of a 2 - basic substance to 2 - 2 - form chirality of 5 - chloro-5 -1 and 2 -methylene tetrahydrofurfuryl alcohol in the presence of a basic substance. The synthetic method is short in route, low in production cost, less in three wastes and suitable for industrial production. (by machine translation)
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- Facile synthesis of controllable graphene-co-shelled reusable Ni/NiO nanoparticles and their application in the synthesis of amines under mild conditions
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The primary objective of many researchers in chemical synthesis is the development of recyclable and easily accessible catalysts. These catalysts should preferably be made from Earth-abundant metals and have the ability to be utilised in the synthesis of pharmaceutically important compounds. Amines are classified as privileged compounds, and are used extensively in the fine and bulk chemical industries, as well as in pharmaceutical and materials research. In many laboratories and in industry, transition metal catalysed reductive amination of carbonyl compounds is performed using predominantly ammonia and H2. However, these reactions usually require precious metal-based catalysts or RANEY nickel, and require harsh reaction conditions and yield low selectivity for the desired products. Herein, we describe a simple and environmentally friendly method for the preparation of thin graphene spheres that encapsulate uniform Ni/NiO nanoalloy catalysts (Ni/NiO?C) using nickel citrate as the precursor. The resulting catalysts are stable and reusable and were successfully used for the synthesis of primary, secondary, tertiary, and N-methylamines (more than 62 examples). The reaction couples easily accessible carbonyl compounds (aldehydes and ketones) with ammonia, amines, and H2 under very mild industrially viable and scalable conditions (80 °C and 1 MPa H2 pressure, 4 h), offering cost-effective access to numerous functionalized, structurally diverse linear and branched benzylic, heterocyclic, and aliphatic amines including drugs and steroid derivatives. We have also demonstrated the scale-up of the heterogeneous amination protocol to gram-scale synthesis. Furthermore, the catalyst can be immobilized on a magnetic stirring bar and be conveniently recycled up to five times without any significant loss of catalytic activity and selectivity for the product.
- Cui, Zhibing,Liu, Jianguo,Liu, Qiying,Ma, Longlong,Singh, Thishana,Wang, Chenguang,Wang, Nan,Zhu, Yuting
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supporting information
p. 7387 - 7397
(2020/11/19)
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- Preparative separation of tetrahydrofurfurylamine enantiomers
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Tetrahydrofurfurylamine enantiomers were separated on a preparative scale by fractional crystallization of diastereoisomeric salts with natural L-tartaric acid. (R)-Tetrahydrofurfurylamine was isolated in 68% yield with an optical purity of more than 98.5% according to the HPLC data.
- Musatov,Kublitskii,Malyshev,Kurilov,Vinogradov
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experimental part
p. 1813 - 1814
(2009/09/25)
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- Syntheses of optically active 2-tetrahydrofuran derivatives
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The resolution of 2-tetrahydrofuran-carboxylic acid and assignment of configuration to the enantiomers are reported.New syntheses of the enantiomers of 2-tetrahydofurancarboxaldehyde are also described.
- Belanger, Patrice C.,Williams, Haydn W. R.
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p. 1383 - 1386
(2007/10/02)
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- Resolution of certain asymmetric primary amines using lasalocid
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Racemic modifications of optically active primary or tertiary amines are treated with lasalocid to form diastereomeric salts. The so-formed diastereomeric salts are separated and, subsequently, can be chemically decomposed to give the desired enantiomers of the amine. The resolving agent, lasalocid, is recovered in this process by precipitation or evaporation from organic solvents.
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