A chiral formamide: Design and application to catalytic asymmetric synthesis

Iseki, Katsuhiko; Mizuno, Shin; Kuroki, Yoshichika; Kobayashi, Yoshiro

doi:10.1016/s0040-4039(98)00334-7

Cited by 110 publications

(18 citation statements)

References 20 publications

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“…The NMR spectrum is identical with that reported in the literature. [43,44] Optical rotation: [α] D 20 = +3.0 (c = 0.68, EtOH) for 48 % ee; ref. [44] [α] D 20 = +9.7 (EtOH) for 98 % ee.…”

Section: -(Cyclohexyl)but-3-en-1-ol [(R)-5l]mentioning

confidence: 99%

Allylation of Aldehyde and Imine Substrates with In Situ Generated Allylboronates – A Simple Route to Enatioenriched Homoallyl Alcohols

Sebelius

Szabó

2005

Eur J Org Chem

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Allylation of aldehyde and imine substrates was achieved using easily available allylacetates and diboronate reagents in the presence of catalytic amounts of palladium. This operationally simple one‐pot reaction has a broad synthetic scope, as many functionalities including, acetate, carbethoxy, amido and nitro groups are tolerated. The allylation reactions proceed with excellent regio‐ and stereoselectivity affording the branched allylic isomer. By employment of commercially available chiral diboronates enantioenriched homoallyl alcohols (up to 53 % ee) could be obtained. The mechanistic studies revealed that the in situ generated allylboronates react directly with the aldehyde substrates, however the allylation of the sulfonylimine substrate requires palladium catalysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

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“…The NMR spectrum is identical with that reported in the literature. [43,44] Optical rotation: [α] D 20 = +3.0 (c = 0.68, EtOH) for 48 % ee; ref. [44] [α] D 20 = +9.7 (EtOH) for 98 % ee.…”

Section: -(Cyclohexyl)but-3-en-1-ol [(R)-5l]mentioning

confidence: 99%

Allylation of Aldehyde and Imine Substrates with In Situ Generated Allylboronates – A Simple Route to Enatioenriched Homoallyl Alcohols

Sebelius

Szabó

2005

Eur J Org Chem

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“…In addition to phosphoramide-based organocatalysts, chiral C 2 -symmetric formamides were found to be versatile catalysts the asymmetric allylation of alde- hydes [173,174]. Interestingly, this organocatalytic approach was found to be complementary to the phosphoramide-catalyzed allylation with regard to substrate range.…”

Section: Chiral Formamides As Organocatalystsmentioning

confidence: 99%

“…Interestingly, this organocatalytic approach was found to be complementary to the phosphoramide-catalyzed allylation with regard to substrate range. In the presence of 20 mol% organocatalyst 163a and 100-200 mol% HMPA allylation of cyclohexylcarboxaldehyde gave the product 159j in 80% yield and with excellent enantioselectivity (98% ee) [173]. For allylation of such substrates the Izeki group developed a suitable formamide-based organocatalyst, 163a.…”

Section: Chiral Formamides As Organocatalystsmentioning

confidence: 99%

Nucleophilic Addition to CO Double Bonds

Berkessel

Gröger

2005

Asymmetric Organocatalysis

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H CN HO 97 %, 97 % ee (ref. 23) 83 %, >98 % ee (ref. 26) H CN HO 61 %, 91 % ee (ref. 23) H CN HO 76 %, 93 % ee (ref. 23) H 3 CO H CN HO 78 %, 96 % ee (ref. 23) H 3 C H CN HO H 3 C 95 %, 91 % ee (ref. 22) H CN HO H 3 CO 83 %, 97 % ee (ref. 23) H CN HO PhO 97 %, 92 % ee (ref. 23) 84 %, 95 % ee (ref. 26) H CN HO 85 %, 83 % ee (ref. 22) H 3 CO H CN HO 45 %, 84 % ee (ref. 23) OCH 3 H CN HO 90 %, 80 % ee (ref. 22) F 3 C H CN HO 50 %, 89 % ee (ref. 22) N H H 3 C O O H O 76 %, 93 % ee (ref. 22) Scheme 6.2 132 6 Nucleophilic Addition to CbO Double Bonds 1: 83 %, 97 % ee (R ) (ref. 23) 2: 89 %, 56 % ee (S ) (ref. 33) t-Bu H O 91 %, 66 % ee (ref. 33) i-Pr H O 83 %, 64 % ee (ref. 33) H O 98 %, 74 % ee (ref. 33) n-C 5 H 11 H O 93 %, 81 % ee (ref. 33)

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“…Catalysts 3 [14] and 4 [15] exhibited high enantioselectivities in additions of aliphatic aldehydes. However, 4 did not show high enantioselectivity in the addition of aromatic aldehydes with allylboronic acid pinacol ester.…”

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confidence: 99%

“…Similarly, (+)-13b to (+)-13d were assigned as (R) too based on the positive OR magnitudes. [17] The addition of allyltrichlorosilane 15 to benzaldehyde (14) was carried out in the presence of (+)-13 near À80 8C for 16 h.The effect of solvents, such as toluene, THF, EtOAc, acetonitrile and dichloromethane on the addition reactions was investigated. The former three solvents led to enantioselectivities from 85-90% but poor conversion (about 10%).…”

mentioning

confidence: 99%