Ichikawa and co‐workers synthesized iminosugars 55, 58, 59, 62, 63, and 65 starting from the available carbohydrates d‐lyxose, d‐ribose, d‐arabinose, and d‐mannofuranose (Scheme 9).30 The synthetic strategy involved regioselective tosylation of protected carbohydrates followed by azidation to afford 53, 56, 60 and 64, respectively. More interestingly, the synthesis of 18 could also take place directly from 16 in a one‐pot reaction. Final deprotection with TFA yielded the target 97 (d‐DFJ) in 96 % yield. Pinacol-Derived Chlorohydrosilane in Metal-Free Reductive Amination for the Preparation of Tertiary Alkylphenolmethyl Amines. The corresponding adducts 21 were transformed into iminosugars 22 and 23 in a two‐step protocol, involving deprotection with an acidic ion‐exchange resin, followed by intramolecular RA using catalytic hydrogenation in acidic medium. This method is sometimes called indirect reductive amination. ), THF, –78 °C, 1.5 h, ii) PPh, Reactions and conditions: i) (a) NaH, BnBr, DMF, (b) AcOH:H, Reactions and conditions: i) 1‐nitrohexane, NEt, orcid.org/http://orcid.org/0000-0002-9899-0836, orcid.org/http://orcid.org/0000-0002-8336-383X, orcid.org/http://orcid.org/0000-0002-6766-4624, I have read and accept the Wiley Online Library Terms and Conditions of Use, Science of Synthesis, Catalytic Reduction in Organic Synthesis, e‐EROS Encyclopedia of Reagents for Organic Synthesis, Iminosugars: from Synthesis to Therapeutic Applications. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. described the first synthesis of enantiomerically pure 1,6‐dideoxy‐l‐nojirimycin in nine steps from l‐xylose with an overall yield of 15 %.26. Godin and co‐workers synthesized iminosugar C‐glycosides with a great degree of structural diversity via cross‐metathesis reactions of N‐protected α‐1‐C‐allyl‐1‐deoxynojirimycin derivatives and a large series of different alkenes.27 Condensation of aldehyde 24 with 2‐naphthalenemethylamine (NAPNH2) followed by reaction with allylmagnesium bromide gave the diastereomerically pure amine 29 (Scheme 7). For reproduction of material from all other RSC journals. E-mail: Enantiospecific synthesis of isomers of AES, a new environmentally friendly chelating agent. https://doi.org/10.1016/j.tet.2010.01.047. Get article recommendations from ACS based on references in your Mendeley library. We can envisage that in the next future the research will take advantage of such novel technologies to further improve the overall method performance. The DRA reaction on 127 was achieved with BnNH2 as the amine source and H2 in the presence of Pd(OH)2/C catalyst, affording 54 in excellent 69 % yield over 4 steps (debenzylation, imine formation, imine reduction and RA over the anomeric carbon). The reductive amination and transamination are two forms of amination processes. The regioselective aziridine ring‐opening with TFA (1 equiv.) The equilibrium between aldehyde/ketone and imine can be shifted toward imine formation by removal of the formed water through physical or chemical means. Francesca Cardona, born 1971, got her PhD in Chemical Sciences with Prof. A. Brandi in 1999. She was awarded permanent researcher at the Department of Chemistry in Florence in 2002, and since 2015 she is Associated Professor. [25] Following this approach, Asano et al. Azomethines. exploiting stereoselective aldol reactions between optically pure Cbz‐protected (S)‐isoserinal acetonide 19 and appropriate hydroxy ketones 20 (Scheme 5).24, The stereoselective syn aldol reaction was achieved successfully by using tertiary amines proline based[24] or Zn/prophenol complexes[24] as aldol catalysts, thus presenting two parallel routes to get optically pure products with good yields and high diastereoselectivity. When intermediate 10 was reduced but not subjected to oxidative cleavage compound 14 was obtained, and afforded 1,5‐dideoxy‐1,5‐imino‐6‐hydroxy‐β‐l‐glycero‐l‐ido‐heptitol (15) in good yield (75 %) through hydrogenation under high pressure (80 psi) in the presence of Pd/C catalyst.20. However, this one‐pot procedure suffered from scarce reproducibility with alkylamines and better results were obtained using NaBH3CN as the reducing agent (in MeOH and in the presence of 3Å MS and CH3COOH). Chiral cyclic amines can be prepared via intramolecular reductive amination of N-Boc-protected amino ketones in a one-pot process. One‐Pot N‐Deprotection and Catalytic Intramolecular Asymmetric Reductive Amination for the Synthesis of Tetrahydroisoquinolines Huan Zhou Department of Chemistry and Chemical Engineering, Northwest A&F University, 22 Xinong Road, Yangling, Shaanxi, 712100 PR China