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Please login to access the full content or check if you have access via31.33.1.6.4 Variation 4: By α-Oxyamination of Aldehydes and Ketones with Proline and Other Asymmetric Organocatalysts
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Schmidt, A., Science of Synthesis, (2007) 31, 1760.
Enantioselective α-oxyaminations of aliphatic aldehydes can be accomplished by reaction with nitrosobenzene in the presence of L-proline;[92–94] a review covers the literature up to 2004.[84] In chloroform, the homodimerization of the aldol and the α-amination pathway is suppressed.[92] The observed enantioselectivities are in accord with the proposed mechanism of the proline-catalyzed aldol reaction, and are rationalized by invoking an E-enamine mechanism operating through a chair transition state.[93] The initially formed aminooxy aldehydes 74 resulting from reaction between aldehydes 73 and nitrosobenzene are supposed to be labile, so that subsequent reduction to 2-aminooxy alcohols 75 is possible in the presence of sodium borohydride (Scheme 34).[92,93] Alternatively, an indium-promoted allylation of the aldehyde group with allyl bromide to give a secondary alcohol,[95] or an in situ alkenation with diethyl (2-oxopropyl)phosphonate can be performed.[96]
Meeeee 88 Meeeeeeee ee 8-(Meeeeeeeee)eeeee-8-eee ee M-Meeeeee-Meeeeeeee Meeeeeeee eeeeeee Meeeeeeee Meeeeeee eee Meeeeeeeeeeeee Meeeeeee ee Meeeeeeee eeee Meeeee Meeeeeeeeee[88,88,88]
M8 | Meeeeee ee Meee 8 | ee (%) ee 88 | Meeee (%) ee 88 | Mee |
---|---|---|---|---|
eMe | MMMe8 | 88 | 88 | [88] |
Me | MMMe8 | 88 | 88 | [88] |
Me | MMMe8 | 88 | 88 | [88] |
(MM8)8MMMMM | MMMe8 | 88 | 88 | [88] |
MMMe8 | 88 | 88 | [88] | |
eMe | MMMM | 88 | 88 | [88] |
Me | MMMM | 88 | 88 | [88] |
Me | MMMM | 88 | 88 | [88] |
(MM8)8MM=MM8 | MMMM | 88 | 88 | [88] |
(MM8)8MMMee | MMMM | 88 | 88 | [88] |
Me | MeMM | 88 | 88 | [88] |
α-Meeeeeeeeeeeee ee eeeeeee 88 ee eeee α-(eeeeeeeeee) eeeeeee 88 eee eeee eeeeeeee ee eeeeeeeeeeeeeeeee,[88,88] eeeeeeeeee,[88] eee eeeeeeee eeeeeeeee[88,88] (Meeeee 88). Meee eeeeeeee ee eeeeeeeeeeeeee eeee eee eeeee eeeeeeee ee eee eeeeeeee[88] eee eeeeee ee ee eeeeeeeee eee eeeeeeeee eeee eeeeee eee eeee eeeeeeeeeeeeeeeeeeee eee ee eeeeeeee eeee eeeeeeeeeeeeeeee ee eee eeeeeeeeeeeeee eee α,α′-eeeeeeeeeeeeeeee. α-(Meeeeeeeeeee) eeeeeee 88 eeee ee eeeeeeeeee (Meeeee 88).
Meeeee 88 M-Meeeeee-Meeeeeee α-Meeeeeeeeeeeee ee Meeeeee ee Meeeeeeeeeeeee[88–88]
M8 | M8 | Meeeee ee M-Meeeeee (eee%) | Meeee (88/MeMM) | Meeeeee | Meee | Meee (e) | Meeee (88/88) | ee (%) ee 88 | Meeee (%) | Mee |
---|---|---|---|---|---|---|---|---|---|---|
M | Me | 88 | 88:8 | MMMe8 | ee | 8–8 | 88:88 | 88 | 88 | [88] |
M | eMe | 88 | 88:8 | MMMe8 | ee | 8–8 | 88:88 | >88 | 88 | [88] |
(MM8)8 | 88 | 88:8 | MMMe8 | ee | 8–8 | >888:8 | >88 | 88 | [88] | |
(MM8)8 | 88 | 8:8 | MMM | 8°M | 8.8 | –e | >88 | 88 | [88] | |
MM8MMM8 | 88 | 8:8 | MMM | 8°M | 88 | –e | 88 | 88 | [88] | |
MM8MMeMM8 | 88 | 88:8 | MMMM | ee | 88 | –e | 88 | 88 | [88] | |
MM8MMe8MM8 | 88 | 8:8 | MMM | 8°M | 8.8 | –e | 88 | 88 | [88] |
e Meee 88 eee eeeeeeee.
M eeeeeeeeeeeeeeeeeeeeeee-eeeee eeeeeeeeeeeeee 88 eee eeee eeee eee eee α-eeeeeeeeeeeeee ee eeeeeeeee eeee ee 8-eeeeeeeeeeeeee, eeeeeeee, eee 8-eeeeeeeeeeeeee, eee eeeeeee eeee ee eeeeeeeeeeeee eee eeeeeeeeeeeeeee-8-eee (Meeeee 88).[888]
Meeeee 88 α-Meeeeeeeeeeeee ee Meeeeeeeeeeeeee-8-eee ee eee Meeeeeee ee e Meeeeeeeeee Meeeeeee[888]
eeeee-8-(eeee-Meeeeeeeeeeeeeeeeee)-M-eeeeeee eee eeee eeee eeee ee ee eeeeeeeeeeeeee ee eee α-eeeeeeeeeeeeee ee eeeeeeee eeeeeeeee.[888] M eeeeeeee eeeeeeeee ee eeeeeee-eeeeeee M-eeeeeeeeeeeeeeeeeeee eee eee eeeeee eeeeeeeee eeeeeeeeee α-eeeeeeeee ee eeeeeeeeeeeee eeee eeeeeeeeeeeeee eee eeee eeeeeeee.[888]
Meeeeeeeeeeeeee α-eeeeeeeeeeee ee eeeeeeeee eeee eeeeeeeeeeeeee eeeeeeeee ee (M)-8-eeeeeeeeee-8-ee-8M-eeeeeeeee (88), eeeeeeee ee eeeeeeeeeeee eeeeee ee ee ee eeee eeeeee eeeeeeeeeeeeeeee eeee eeeee 8,8-eeeeeee-8M-8,8-eeeeeeee 88 (Meeeee 88).[888]
Meeeee 88 Meeeee Meeeeeeeeeeeee ee Meeeeeeee α-Meeeeeeeeeee ee Meeeeeeee[888]
M8 | ee (%) | Meeee (%) | Mee |
---|---|---|---|
Me | 88 | 88 | [888] |
(M)-MM8MM=MM(MM8)8Me | 88 | 88 | [888] |
(MM8)8MM8Me | 88 | 88 | [888] |
eMe | 88 | 88 | [888] |
Me | 88 | 88 | [888] |
e-Me | 88 | 88 | [888] |
Meeeeeeeeeee Meeeeeeeee
(M)-8-(Meeeeeeeee)-8-eeeeeeeeeee-8-ee (88, M8 = eMe):[88]
Me e eee-eeee eeee eeeeeee eeee M-eeeeeee (8 eee%) eee eeeee MMMe8 (8.8 eM) eee eee eeeeeeeeee eee eeeeee ee 8°M. Meeee 88 eee, MeMM (888.8 ee, 8 eeee) eee eeeee ee eee eeeeeee, eeeeeeeee eee eeeee ee eee eeeeeeeeee eeeeeee ee eeeee. 8-Meeeeeeeeeeee (88, M8 = eMe; 8.888 eM, 8.8 eeee) eee eeee eeeee ee eee eeeeeee. Meeeeeee ee 8°M eee eeee eeeeeeeee eeeee eee eeeeeeee eee eeeeeeeee (MMM eeeeeeeeee) eee eee eeeee eeeee eeeeeeeeeee (8 e). Mee eeeeeee eee eeee eeeeeeeeeee ee e eeeeeeeeee ee MeMM8 ee MeMM ee 8°M. Meeee 88 eee, eee eeeeeee eee eeeeeee eeee eee. ee MeMMM8, eee eeeeeeeee eeee MM8Me8 (8 × 88 eM); eee eeeeeee eeeeeeee eee eeeee (Me8MM8), eeeeeeee, eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Meeeeeeeeeee eee eeeeeeeeeeee ee eeeeee eeeeeeeeeeeeee; eeeee: 888.8 ee (88%); 88% ee. (Mee eeeeeeeeeeeeeeeeee eee eeeeeeeeee ee eeeeee MMMM eeeeeeee.)
(M)-8-(Meeeeeeeee)-8-eeeeeeeeeeee-8-ee (88, M8 = Me):[88]
Me e eeee ee 8-eeeeeeeeeeeeee (88, M8 = Me; 888.8 ee, 8.8 eeee) eee MeMM (888.8 ee, 8 eeee) ee eeeee MMMM (8 eM), M-eeeeeee (88 eee%) eee eeeee. Mee eeeeeee eee eeeeeeeeee eeeeeee ee ee eee 88–88 eee. Mee eeeeeeee eee eeeeeeee eeee eee eeeee eeeeeee eeee eeeee ee eeeeee. Mee eeeeeee eee eeee eeeeee eeee e eeeeeee ee MeMM8 (888.8 ee, 8.8 eeee) ee eeeee MeMM (8 eM). Meeee eeeeee, eee eeeee eeeeeee eee eeeeeeeeeeeeeee (eeeeee eee); eeeee: 888.8 ee (88%); 88% ee. (Mee eeeeeeeeeeee eeeeee eee eeeeeeeeee ee eeeeee-eeeee MMMM.)
(M)-8-(Meeeeeeeee)eeeeee-8-ee (88, M8 = Me):[88]
M-Meeeeee (88.8 ee, 8.88 eeee) eee eeeee ee e eeee ee eeeeeeee (88, M8 = Me; 888 μM, 8.8 eeee) eee MeMM (88.8 ee, 8.8 eeee) ee MeMM (8 eM) ee −88°M. Meeee eee eeeeeee eee eeeeeee eee 88 e ee −88°M, MeMM (8 eM) eee MeMM8 (88.8 ee, 8.8 eeee) eeee eeeee, eee eeeeeeee eeeeeeeee eee 88 eee ee −88°M. Meeee eeeeeeee ee eeeeeeeee eeeeee, eee eeeeeee eeeeeeeee eeee eeeeeeeee eeee MeMMe (8 ×) eee eee eeeeeeee eeeeeee eeeeee eeee eeeee (Me8MM8). Mee eeeeeee eee eeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, MeMMe/eeeeee); eeeee: 88.8 ee (88%); 88% ee.
(M)-8-(Meeeeeeeee)-8,8-eeeeeeeeeeeeeeeeeeeee (88, M8,M8 = MM8MMe8MM8):[88]
M eeee ee MeMM (88.8 ee, 8.8 eeee) ee MMM (8.8 eM) eee eeeee eeee 88 e ee e eeeeeee eeee ee e eeee ee 8,8-eeeeeeeeeeeeeeeeeeeee (88, M8,M8 = MM8MMe8MM8; 888.8 ee, 8.8 eeee) eee M-eeeeeee (8.8 ee, 8.88 eeee) ee MMM (8.8 eM) ee 8°M, eee eee eeeeeee eee eeee eeeeeee eee e eeeeeee 88 eee ee 8°M. Mee eeeeeeee eee eeeeeeee eeee eeeeeeeee eeeeee eeee (eM 8), eee eee eeeeeee eeeeeeeee eeee eeeeeeeee eeee MeMMe (8 ×). Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeee eeeee, eeeee (Me8MM8), eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee, eee eee eeeeeee eee eeeeeeeeeeeeeee (eeeeee eee, MeMMe/eeeeee 8:88 ee 8:8); eeeee: 888.8 ee (88%); 88% ee (ee eeeeee MM eeeeeeee).
(M)-8-(Meeeeeeeee)eeeeeeeeeeeee [88, M8,M8 = (MM8)8]:[88]
Meeeeeeeeeeee [88, M8,M8 = (MM8)8; 8 eM, 88 eeee)] eee eeeee ee e eeee eeeeeeeeee MeMM (888 ee, 8 eeee) eee M-eeeeeee (88 ee, 8.8 eeee) ee MMMe8 (8 eM). Meeee 8 e ee eeeeeeee eeeeeeee, eee eeeeeeee eee eeeeeeee ee eee eeeeeeee ee ee MM8Me, eee eee eeeeeee eeeee eee eeeeeeeee eeee MeMMe (8 ×). Mee eeeeeeee eeeeeee eeeeee eeee eeeee (MeMM8) eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee, eee eee eeeeeee eee eeeeeeeeeeeeeee (eeeeee eee, MeMMe/eeeeeee 8:8); eeeee: 888 ee (88%); 88% ee.
(M)-8-Meeeeeeee-8-eeeeee-8,8-eeeeeee-8M-8,8-eeeeeee (88, M8 = eMe):[888]
Me e eeee ee 8-eeeeeeeeeeeee (8.88 e, 8.88 eM, 8.88 eeee) ee MMMM (88 eM) eee eeeee 88 (88 ee, 8.88 eeee). Mee eeeeeeeee eeeeeeeeee eee eeeeeee eeeeeeeeee eee 8 eee eeeeee eeeeeeee ee MeMM (8.88 e, 8.88 eeee). Mee eee ee eee eeeeeeee eee eeeeeeeeeee ee e eeeeee ee eeeee eeee eeeee ee eeeeee eee eee eeeeeeeee ee MMM. Mee eeeeeee eee eeee eeeeee ee 8°M, eee MMM (88 eM) eee eeeee, eeeeeeee ee [Me8MMM=MM8]Me (8.88 e, 8.88 eeee) eee eeee MeM (8.88 e, 8.88 eeee). Meeee 88 eee ee eeeeeeee ee 8°M, eee eeeeeee eee eeeeeeee eeee eee. ee MM8Me eee eeeeeeeee eeee Me8M (8 × 88 eM). Mee eeeeeeee eeeeeee eeeeee eeee eeeee (MeMM8), eeeeeeee, eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeeeee eeeeeee eee eeeeeeee ee eeeee eeeeee eeeeeeeeeeeeee (eeeeeeeee eeeee/eeeeeee 8:8); eeeee: 8.88 e (88%); 88% ee; [α]M88 +88.8 (e 8.88, MMMe8).
References
[84] | Meeee, M. M., Meeee. Meee., (8888) 888, 8888; Meeee. Meee. Mee. Me., (8888) 88, 8888. |
[92] | Meeee, M. M.; Meeeee, M. M.; Meee, M. M.; MeeMeeeee, M. M. M., M. Me. Meee. Mee., (8888) 888, 88888. |
[93] | Meeee, M., Meeee. Meee., (8888) 888, 8888; Meeee. Meee. Mee. Me., (8888) 88, 8888. |
[94] | Móeeeee, M.; Meeeée, M.; Møeeeee, M.; Meeeeeeee, M.; Meee, M., Meee.–Mee. M., (8888) 88, 8888. |
[95] | Meeee, M., Meee. Meeeee. (Meeeeeeee), (8888), 888. |
[96] | Meeee, M.; Me, M., Mee. Meee., (8888) 8, 8888. |
[97] | Meeeeee, M.; Meeeeeeee, M.; Meeeee, M.; Meeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[98] | Meeeeee, M.; Meeeeeeee, M.; Meeeee, M.; Meeee, M., Meeee. Meee., (8888) 888, 8888; Meeee. Meee. Mee. Me., (8888) 88, 8888. |
[99] | Møeeeee, M.; Meeeée, M.; Móeeeee, M., Meeee. Meee., (8888) 888, 8888; Meeee. Meee. Mee. Me., (8888) 88, 8888. |
[100] | Meee, M.; Meee, M.; Me, M.; Meee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[101] | Meeeeee, M.; Meeeeeeee, M.; Meeeee, M.; Meeeee, M.; Meeeeeee, M.; Meeee, M.; Meeeeeeee, M.; Meeeeee, M., Mee. Meeee. Meeee., (8888) 888, 8888. |
[102] | Meeeée, M.; Meeeee, M.; Meeeeee, M.; Meeeeeeee, M.; Móeeeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[103] | Meeeee, M.; Meee, M. M.; Meeeeeeeee, M. M.; Mee, M. M., Mee. Meee., (8888) 8, 8888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) 88/8, 8888.