Stereo- and regiochemical aspects of the Mitsunobu reaction in synthesis of chiral amino ether ligands for asymmetric reactions

Okuda, Mitsuru; Tomioka, Kiyoshi

doi:10.1016/s0040-4039(00)60736-0

Cited by 49 publications

(15 citation statements)

References 13 publications

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“…Treatment of b-amino alcohol 119 with PPh 3 /1,1 0 -(azodicarbonyl)dipiperidine (ADDP) in the presence of 2-methoxyphenol led to ethers 120 and 121 in a 96/4 ratio in favour of 120 (92% yield) (nucleophilic attack on the aziridinium intermediate at C-2) (Scheme 38). 50 The use of acetyl chloride also promoted the rearrangement of b-amino alcohol 104. Whereas ester 123 was obtained as the major product (58% yield), the rearranged ester 122 was isolated in moderate yield (15%).…”

Section: R 2 = Arylmentioning

confidence: 99%

Rearrangement of β-amino alcohols via aziridiniums: a review

et al. 2010

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This tutorial review focuses on the rearrangement of b-amino alcohols via aziridinium intermediates. It covers the literature from 1947 to January 2009 (55 references). The rearrangement of b-amino alcohols can be performed by activation of the hydroxy group followed by the addition of nucleophiles (Nu). In most examples, an aziridinium intermediate is involved in the rearrangement. The ratio of amines resulting from the attack of nucleophiles at either the C-1 or C-2 position of the aziridinium intermediate, depends on the nature of the nucleophiles and the R 2 substituent. In some cases, solvent as well as temperature can influence the ratio of amines.Aziridines have been extensively used as useful building blocks. 1,2 The control of the regio-and stereoselectivity in the opening of aziridines provides convenient access to chiral nitrogen-containing compounds. [3][4][5][6] Although N,N-dialkyl aziridiniums are stronger electrophiles than neutral aziridines, their use as key intermediates in organic synthesis is rare. [7][8][9] Aziridiniums, generally obtained through activation of b-amino alcohols, can be opened by a wide range of nucleophiles with or without rearrangement depending on the regioselectivity of the nucleophilic attack.This review covers only the rearrangement of b-amino alcohols of type A, B, and C (Fig. 1) as the rearrangement of prolinols of type D has been recently covered. 10

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Section: R 2 = Arylmentioning

confidence: 99%

Rearrangement of β-amino alcohols via aziridiniums: a review

et al. 2010

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“…To this end ligands 24-27, which are structurally similar to the diether 8 and have had success in other reactions, were synthesised by literature methods. [24][25][26][27] The observed trend in selectivity (Table 7) is in keeping with the addition of alkyllithiums to imines, 28 with amine 24 giving little selectivity and amine 27 giving the highest. When this ligand was applied to a range of nucleophiles and aldehydes the selectivity diminished (Table 8).…”

Section: Investigations Into Amine Ligandsmentioning

confidence: 63%

Ligand-mediated enantioselective addition of lithium carbazolates to aldehydes

et al. 2006

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The enantioselective synthesis of acyclic pyrrole, indole and other N-carbazole carbinols via ligand-mediated addition of lithium carbazolates to aldehydes, together with studies into their catalytic enantioselective synthesis using substoichiometric base and ligand, are reported. The subsequent exploitation of the resulting stereocentre as a controlling element in 1,3-syn- and anti-selective reduction of beta-ketones and elaboration to homoallylic alcohols is also described.

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“…The reaction mediated by (−)-sparteine ( 2 ) gave ( S )- 6a in 15% ee and 85% yield after 3 h at −20 °C. Fortunately, we found that the chiral amino ether 3 gave ( S )- 6a in a reasonably good ee of 71% and 99% yield after 3 h at −20 °C. In the absence of lithium thiophenolate the reaction mediated by 3 is sluggish, giving 6a in 0.5% yield after 6 days at room temperature.…”

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confidence: 91%