3886-70-2Relevant articles and documents
A METHOD FOR PREPARATION OF DIASTEREOMERIC LACTATE SALTS OF 1-(1-NAPHTHYL)ETHYL AMINE AND PURE ENANTIOMERS OF 1-(1-NAPHTHYL)ETHYL AMINE
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Paragraph 0048, (2021/09/11)
The invention relates to method for preparation of pure enantiomers of 1-(1-naphthyl)ethyl amine by preparing lactate salt with chiral lactic acid as resolving agent. The method comprises reaction of L-lactic acid or D-lactic acid with racemic 1-(1-naphthyl)ethyl amine to form diastereomeric salts of (R/S)-1-(1-naphthyl)ethyl amine-(D/L)-lactate from which pure enantiomer is isolated. The invention also comprises method for preparation of compound with enriched enantiomers of 1-(1-naphthyl)ethyl amine from the mother liquor separated from the diastereomeric lactate salt. The enriched enantiomer is reacted with pure enantiomers of mandelic acid or lactic acid, preferably D-mandelic acid or L-mandelic acid and converted to diastereomeric mandelate salt. Pure (R)- or (S)-1-(1-naphthyl)ethyl amine is obtained from the diastereomeric mandelate salt. The chiral purity of pure enantiomer obtained is between 99% and 100%.
Enzymatic Primary Amination of Benzylic and Allylic C(sp3)-H Bonds
Jia, Zhi-Jun,Gao, Shilong,Arnold, Frances H.
supporting information, p. 10279 - 10283 (2020/07/27)
Aliphatic primary amines are prevalent in natural products, pharmaceuticals, and functional materials. While a plethora of processes are reported for their synthesis, methods that directly install a free amine group into C(sp3)-H bonds remain unprecedented. Here, we report a set of new-to-nature enzymes that catalyze the direct primary amination of C(sp3)-H bonds with excellent chemo-, regio-, and enantioselectivity, using a readily available hydroxylamine derivative as the nitrogen source. Directed evolution of genetically encoded cytochrome P411 enzymes (P450s whose Cys axial ligand to the heme iron has been replaced with Ser) generated variants that selectively functionalize benzylic and allylic C-H bonds, affording a broad scope of enantioenriched primary amines. This biocatalytic process is efficient and selective (up to 3930 TTN and 96percent ee), and can be performed on preparative scale.
Catalytic Reductions Without External Hydrogen Gas: Broad Scope Hydrogenations with Tetrahydroxydiboron and a Tertiary Amine
Korvinson, Kirill A.,Akula, Hari K.,Malinchak, Casina T.,Sebastian, Dellamol,Wei, Wei,Khandaker, Tashrique A.,Andrzejewska, Magdalena R.,Zajc, Barbara,Lakshman, Mahesh K.
supporting information, p. 166 - 176 (2020/01/02)
Facile reduction of aryl halides with a combination of 5% Pd/C, B2(OH)4, and 4-methylmorpholine is reported. Aryl bromides, iodides, and chlorides were efficiently reduced. Aryl dihalides containing two different halogen atoms underwent selective reduction: I over Br and Cl, and Br over Cl. Beyond these, aryl triflates were efficiently reduced. This combination was broadly general, effectuating reductions of benzylic halides and ethers, alkenes, alkynes, aldehydes, and azides, as well as for N-Cbz deprotection. A cyano group was unaffected, but a nitro group and a ketone underwent reduction to a low extent. When B2(OD)4 was used for aryl halide reduction, a significant amount of deuteriation occurred. However, H atom incorporation competed and increased in slower reactions. 4-Methylmorpholine was identified as a possible source of H atoms in this, but a combination of only 4-methylmorpholine and Pd/C did not result in reduction. Hydrogen gas has been observed to form with this reagent combination. Experiments aimed at understanding the chemistry led to the proposal of a plausible mechanism and to the identification of N,N-bis(methyl-d3)pyridin-4-amine (DMAP-d6) and B2(OD)4 as an effective combination for full aromatic deuteriation. (Figure presented.).