Catalytic enantioselective borane reduction of arylketones with pinene-derived amino alcohols

New 1,3-amino alcohols derived from enantiopure bridgehead β-aminobicyclo[2.2.2]oct-5-ene-2-carboxylic acids

“…Synthesis of enantiopure amino alcohols is of great importance in synthetic organic chemistry since they are a well established source of ligands for asymmetric synthesis (Blaser 1992;Ager et al 1996;Lait et al 2007) including enantioselective borane reduction of prochiral ketones (Corey et al 1987;Corey and Helal 1998;Deloux and Screbnik 1993;Li et al 1999;Krzemiński and Wojtczak 2005;Krzemiński and Zaidlewicz 2003;Hobuss et al 2008) or enantioselective addition of dialkylzinc (Kitamura et al 1986;Kossenjans and Martens 1998;Garcia Martinez et al 2002;Oliveira and Costa 2004;Szakonyi et al 2006;Binder et al 2009;Scarpi et al 2009;Wu et al 2009). Apart from this property, enantiopure amino alcohols are also important derivatives for the synthesis of various chemical compounds.…”

A DFT study of the enantioselective reduction of prochiral ketones promoted by pinene-derived amino alcohols

“…[3][4][5][6][7][8] Much effort has been made in designing and developing various kinds of chiral catalysts. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] Recently, Hobuß et al reported an experimental methodology employing pinene-derived amino alcohols, such as 1 (Scheme 1), as efficient chiral catalytic sources for the borane-mediated asymmetric reduction of prochiral ketones. 23 However, no report of theoretical investigations regarding the mechanism of the title reaction has been found.…”

Towards chiral diamines as chiral catalytic precursors for the borane-mediated enantioselective reduction of prochiral ketones

“…IR spectra were recorded on Jasco-FT-IR model 5300. 1 H NMR (400 MHz) and 13 C NMR (100 MHz) spectra were recorded in deuterochloroform (CDCl 3 ) on a Bruker-Avance 400 spectrometer using tetramethylsilane (TMS, δ = 0) as an internal standard. Elemental analyses were recorded on a thermo Finnigan Flash 1112 analyzer.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] We have been working in this direction for the past few years and developed some novel chiral catalysts mainly built on the (2S)-2-anilinomethylpyrrolidine framework (3) for boranemediated asymmetric reduction processes. [13][14][15][16][17][18][19][20][21] In continuation of our efforts in designing and developing useful chiral catalysts for the borane-mediated asymmetric reduction of prochiral ketones we report here the application of two chiral diamines (3S)-3-anilinomethyl-1,2,3,4-tetrahydroisoquinoline (1) and (2R)-2-anilinomethylpiperidine (2) as chiral precursors (catalytic sources) for reduction of prochiral ketones to provide the resulting secondary alcohols in reasonably good enantioselectivities.…”