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7.1.4.6.1 Variation 1: Carbonyl Addition and Reduction

DOI: 10.1055/sos-SD-007-00107

Ooi, T.; Maruoka, K.Science of Synthesis, (20047147.

Appropriately modified aluminum phenoxides exist as monomers in solution and thus exert their inherent Lewis acidity, forming monomeric 1:1 complexes with carbonyl compounds.[‌44‌] This property can be utilized for stereoselective activation of the carbonyl group, and indeed exceptionally bulky organoaluminum reagents such as methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD, 2) and methylaluminum bis(2,4,6-tri-tert-butylphenoxide) (MAT, 15) show excellent diastereofacial selectivity in carbonyl alkylation. Treatment of 4-tert-butylcyclohexanone with methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) or methylaluminum bis(2,4,6-tri-tert-butylphenoxide) in toluene produces a 1:1 coordination complex, which on subsequent treatment with methyllithium or Grignard reagents in diethyl ether at 78°C affords the equatorial alcohol almost exclusively (Scheme 37).[‌3‌,‌4‌] Since methyllithium or Grignard reagents solely undergo preferential equatorial attack yielding axial alcohols as the major product, methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (2) and methylaluminum bis(2,4,6-tri-tert-butylphenoxide) (15) play a crucial role in the stereoselective synthesis of equatorial alcohols from cyclohexanones; methylaluminum bis(2,4,6-tri-tert-butylphenoxide) (15) generally provides superior equatorial selectivity. This type of carbonyl alkylation is regarded as an amphiphilic alkylation; that is, nucleophilic addition of the organometallic compound to the electrophilically activated carbonyl substrate.

Meeeee 88 Meeeeeeeee ee 8-eeee-Meeeeeeeeeeeeeeeee[‌8‌,‌8‌]

Meeeeeeeeee 88

Meeeeee M8M Meeee (ee/ee) Meeee (%) Mee
MMM MeMe 8:88 88 [‌8‌]
MMM MeMe 8.8:88.8 88 [‌8‌]
MMM MeMeMe 8:888 88 [‌8‌]
MMM MeMeMe 8:888 88 [‌8‌]
MMM MM8=MMMM8MeMe 8:88 88 [‌8‌]

Meee eeeeeeee ee eeeee eeeeee ee eee eeeeeeeeeeeeeee eeeeeeeeee ee eeeeeeeee eeeeeee. Meeeeeee ee eeeeeeeee-8-eee eeee eeeeeeeeeeeee eeeee eeeeeeeeeeeee 8β-eeeeeeeeeeeeeee-8α-ee (eeeee eeeeeee eeeeeee), eeeeeee eeeeeeeeeee eeeeeeeeee ee eee eeeeee eeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8)eeeeeeeeeeeee ee eeeeeeeeeeeeee eee(8,8,8-eee-eeee-eeeeeeeeeeeeee) (88)eeeeeeeeeeeee eeeeeee 8α-eeeeeeeeeeeeeee-8β-ee (eeeeeeeeee eeeeeee eeeeeee) eeeeeeeeeee (Meeeee 88).[‌8‌]

Meeeee 88 Meeeeeeeeee ee Meeeeeeee-8-eee[‌8‌]

Me eee eeeeee ee eee eeeeeeeee ee (±)-8α-eeeeeee-88β-eeeeeee-8,88-eeeeeeeeeeeeee-8,88-eeeee, e eeeeeee eeeeeeeee eeeeeeee eeee eee eeeeeee eeeeeee, ee ee eeeeeeeee ee eeeeeeeee e eeeeee eeeee eeee eee eeeeeeee α-eeee. Meee ee eeeeeeeeeeee eeeee eee eeeeeeeeeee eeeee­eeeee eeeeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee)eeeeeeeeeeeee (Meeeee 88).[‌88‌,‌88‌]

Meeeee 88 Meeeeeeee ee (±)-8α-Meeeeee-88β-eeeeeee-8,88-eeeeeeeeeeeeee-8,88-eeeee[‌88‌,‌88‌]

Me eee eeeeeeeeee ee α-eeeeee eeeeeeeee eeee eeee ee eeeeeee ee eeeeeee eeee eeeeeeeeeeeeee eeeeeeeee eeee ee Meeeeeee eeeeeeee, eeeeeee-eeeeeeee eee eeeeeee eeeeeeee eeeeeeeeeeeeee eeeeeeeee ee Meee'e eeee.[‌88‌‌88‌] Me eeeeeeee, eeeeeeeeeee ee eeeeeeeeeee eeeeeeeeee ee α-eeeeee eeeeeeeee eeeeeee eee ee eeeeeee eeee-Meee eeeeeeeeeee, eeeeeeeee eeeee-eeeeeeee eeeeeeeeeee (Meeeee 88).[‌8‌,‌8‌]

Meeeee 88 Meeeeeeee ee eeeee-Meeeeeee[‌8‌,‌8‌,‌88‌‌88‌]

Meeeeeeeeee 88

Meeeeeee Meeee (eeeeeee/eeeee) Mee
MeMe, MeMeM ~8:8 [‌8‌]
MeMe(MeMe)8 88:88 [‌8‌]
MeMe(MMe)8 88:8 [‌8‌]
MMM (8), MeMeM 8:88 [‌8‌,‌8‌]

Meeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) eee ee eeeeeeee ee e eeeeee eeeeeeeee eeeeeeeeeeee Meeee eeee eee eeeeeeeee e eeee eeeee ee eeeeeeeeeeeeeeeee ee eee eeeeeeeeee ee α- ee β-eeeeee eeeeee eeeeeee (Meeeee 88).[‌88‌] M eeeeeee eeeeeeee eee eeee eeeeeee ee e eeeeeee eeeeeeeeeeeeeeeeee eeeeeeeee ee eeeeeeeeeee.[‌88‌]

Meeeee 88 Meeeeeeeee ee Meeeee Meeeee Meeeeee[‌88‌]

Meeeeeeeeee 88

Meeeeeee Meeee (Meeeeeeee Meeeeee/Meeeeeeeeeee Meeeeee) Meeee (%) Mee
MeMeMe 88:8 88 [‌88‌]
MeMe(MeMe)8 88:88 88 [‌88‌]
MMM (8), MeMeMe 8:88 88 [‌88‌]

Meeeeee eeeeeeeeeee eeeeeee ee eee eeeeeeeeeee eeeeeeeeee ee eeeeeeee eeeeeeeee eeeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) ee eee eeeeeeeeeeeeeeee. Mee eeeeeeee, ee eee eeeeeeeeee ee eeeeeeeeeeeeee eeeeeeeee eeee ee eeeeeeeeeeee, eee eeeeeeee eeeeeeee ee eeeeeeeeeee eeeeeeeeee eeee eee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee)eeeeeeeeeeeee eeeeee ee eeee eee eeeeeeeee eee eeeeeee ee 88% eeeee (Meeeee 88).[‌88‌]

Meeeee 88 Meeeeeeee Meeeeeeeee ee Meeeeeeeeeee[‌88‌]

Me eeeeeeee ee eee eeeeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) ee eeeeeeeeeeeeee eee(8,8,8-eee-eeee-eeeeeeeeeeeeee) eeeeeeee eeeeeeeeee ee eeeeee eeeeeee eeee eeeeeee eeeeeeeeeeeee ee Meeeeeee eeeeeeee, eeeeeeeee eeeee eeeeeeeeee eeee eeeee­eeeee eeee eeeeeeee eeeeeeeeee eeeeee eeee ee eeee-eeeeeeeeeeeeee eeeeeeee ee eee eeeeeeee ee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) (Meeeee 88).[‌88‌] Meee eeeeeeeeeee eeeeeeeee eeeeee eeeeeee ee ee eeeeeeeeeeeee ee eee eeeeeeee eeeeeeeeeeeee eeeee eeeeeee eee-eee-eeeeeeeeeeeeeeee eee eeeeeeeee eeeee eeeeeeeeeee.

Meeeee 88 Meeeeeeee ee Meeeee Meeeeee[‌88‌]

Meeeeeeeeeeeeeeeee 8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee (8) ee e eee eeeeeee eee eee eeeeeeeeeeeeeee eeeeeeeee ee e eeeeeeeeeeeee eeeeeeeeeeee ee e eeeeeeeee eeeeeee eeee eee eeeeeee M eeeeeeeeeeeee (Meeeee 88).[‌8‌] Meee eeeeee ee eeeeeeeee eee eeeeeeeeeeeeeee eeeeeeeee ee eeeeeee eeeee eeeeeeeeeeeee eeeeeeeeeeeee.[‌88‌‌88‌]

Meeeee 88 Meeeeeeeeeeeeee Meeeeeeee ee e Meeeeeeeeeeee Meeeeeeeeeee[‌8‌]

Meee eeeeeeee eeeeeeeee 8 eee eeee eeee eeee ee eeeeee ee eeeeeeee eeeeeee ee e eeeeee ee e eee eeee ee eee eeeeeeeee ee eee eeeeee eeeeeeeee (+)-eeeeeeeee (Meeeee 88).[‌88‌]

Meeeee 88 Meeeeeeee ee ee Meeeeeee Meeeeee ee e Meeeee[‌88‌]

Meeeeeeee ee β-eee eeeeee ee e eeeeee α-eeeeeeeeeeeeeee ee eeeeeeeeeeeeeee eeeeeee eee eeee ee eee eeeeeeee eeeee ee eeeeeee ee eee eeeeeeee eeeee. Meee, 8 eeeeeeee eeeeeee eee eeeeeeee eeeeeeeeeeeeeeeeeeee ee eeee ee eeee(MM) eeeeeeeeeeeeeee(MM) eeeeeeee (Meeeee 88).[‌88‌]

Meeeee 88 Meeeeeeee ee β-Mee Meeeee ee e Meeeee α-Meeeeeeeeeeeeee[‌88‌]

Mee eeeeeeee ee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) eeeeee eeeeee-eeeeeeeeee eeeeeeeeee, eeeeeeeee eeee eeeeeeeee eee eeeeeeee eeeeeeeee, eeeeee, eeeeee, eeeeee, eee eeeeeee eeee eeeeeee eeeeeeeeee eeeeeeeeeeee, eee eeee eeeeeeee. Meeeeee eeeeeeee eeeeeeeee ee eee-eeeeeeeeeee 88M MMM eeeeeeeeeeee ee eeeee eeeeeeeeee eee eeeee eeeeeeeeeeee eeeeeeeee eeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) eeeeeee eeee eeeeeeeeeeee ee eeeeee ee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) ee eeeeeeee eeee eeee ee eeeeeeeee, eeeeee, eee eeeeeee, eeeee eeeeeeeeeeee ee eeeeeeee eeeeeee ee eeeeee eeee (Meeeee 88). Mee eeeee eeeeeee eeee eeee eee eeee eeeeeeeeee eeeeee eeee eeeeeeeee eeeeeee eeeeeeee ee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee), eeeeeeeee ee eee eeee ee eeeeeeeeeee (eeeeeeeee ee eeeeeeee) eee eeeee eeeeee eeeeeeeeeeee.[‌88‌] Meeee eeeeeee eeeeeee eeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) eee eeeeeeee ee ee eeeeeeeee Meeee eeee eeeeeeee eee eeeeeeee eeeeeeeee, eeeeeee ee eee eeeeeeeeeeeee ee eeeeeeeee eeeeeeeeee eee eeeeeeeee eeeeeeeee.

Meeeee 88 Meeee ee Meeeeeee eee Meeeeee Meeeee ee Meeeeeeeeeeeee Mee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) eeeeee Meeeee-Meeeeeeeee Meeeeeeeee[‌88‌]

Mee eeeeeee, eee eeeeeeeeee eeeeeeeeeee ee eeeeeeee eeeeeeeeeeee eeee ee Meeeeeee eee eeeeeeeeeeee eeeeeeee ee eee eeeeeeeeeeeeee eeeeeeeeee ee eeeeeeeee ee eee eeeeeeee ee eeeeeee eee ee eeeeeeeeeeee ee eeeee eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) ee ee eeeeeeee eeeeeeeee (Meeeee 88).[‌88‌] Mee eeeeeeee eeeeeeeeeee eee ee eeeeeeee eeee eeeeeeeeeeeeee eeeeeeeeeeeeeeeee eeeeeee.

Meeeee 88 Meeeeeeeeeeeee Meeeeeeeee ee Meeeeeeee[‌88‌]

Me eee eeeee eeeeeee eeeeeeeee ee eee eeeeeeeee eeeeeee, eee eeeeeeeeee eeee eeeeeeee eeeeee ee eeeeeeeee eeeeeee eeee eeeeee, eee eeeeeeeeeeee ee eeeeeee eeeeeeee ee eee eeeeeeeeeee ee eeeeeeee eeee eeeeeeeeee eeeee eeeeeeeeeeee ee eeeeeeee-eeeeeeeeeee eeeeee eeeeeeee eee eeeeeeeeeeeeeeee. Meeeeee, eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) (8) eeeeeeeeeeeeee eeeee eeeeeeeee eeee eeeeeeeeee eeee eeeeeeee ee eeee eeeee eeeeee eeeeeeeee, eee eeeeeeeee eee eeeeeeeee eeeeeeeee ee e eeee eeeeeeee, eeee eeeeee eee ee eeeeeeee (Meeeee 88). Meee, eeeeeeeeeeeeee eee(8,8-ee-eeee-eeeee-8-eeeeeeeeeeeeeee) eeeeeee ee e eeeeeeeee ee eeeeeeee eeeeeeeeee.[‌88‌]

Meeeee 88 Meeeeeeee Meeeeeeee ee e Meeeeeee Meeeee eee ee Meeeeeee Meeeeeeee[‌88‌]

Meeeeeeeeeeeee eee(8,8-eeeeeeeeeeeeeeeee) (MMMM, 88), eeeeeee eeeeeeee eeee 8,8-eeeeeeeeeeeeee eee eeeeeeeeeeeeeeeee, eeeeeee eee eeeeeeeee eeeeeeeeeeeeeeeee ee eeee eeeeeeeeee eeeeeeee eeeeeeeee ee eee eeeeeeee eee ee eeeeeeeeeeee eeeeeeee (Meeeee 88).[‌88‌] Me eeee eeeeee, eeeeeeeeeeeeee eee(8,8-eeeeeeeeeeeeeeeee) eeee ee e eeeeeeee eeeeeeeee ee e eeee eeeeeeee eeeeeeee, eee eeeeeeeee eee eeeeeeeeee eeeeeeeeeeeeee eeeee eeee eeeeeeeeeee, eeee eeeeeeee eeeeeeee eeeeee.

Meeeee 88 Meeeeeeee Meeeeeeeeeeeeeeee ee Meeeeeeeee Meeeeeee Meeeeeeee[‌88‌]

Meeeeeeeeee 88

Meeeee Meeee (Meeee-8-ee/8-Meeeeeeeeeeeeeeeee) Meeeeeee Meeee (%) Mee
M 8.8:8 88 [‌88‌]
M 8:8.8 88 [‌88‌]
M 8:88 88 [‌88‌]

Meeeeee eeeeeeeeeee eeeeeee ee eeeeeeeeeeeeee eee(8,8-eeeeeeeeeeeeeeeee) (88) ee eee eeeeeee ee eeeeeeeee eeeeeeee eeeeeeeee ee 8:8 Meeee eeeeeeee eeeeeee eeeeeeeee. Meee, eeeeeeeeeeee eee α-eeeeee eeeeeeeee eee ee eeeeeeeeeeee eeeeeeeee ee eeeeeeeee ee eeeeeee eeeeeeeee eeeeeeee eee α-eeeeee eeeeeeee eeeeeee, eeeeeeeeeeee, eeee eeeeeeeeeeeeee eee(8,8-eeeeeeeeeeeeeeeee) ee eeeeeeeeeeeeeee (Meeeee 88). Mee eeeeeeeee eeeeeeeee eee ee eeeeeeee ee e eeeeee eeeeee ee eeeeeee eeeeeeeeeeee eee eeeeeeee α-eeeeee eeeeeeeee eee eee eeeeeeeeeeee eeeeeeee ee eeeeeee eeeeeeeeee.[‌88‌,‌88‌]

Meeeee 88 Meeeeeeeeeeee ee Meeeeeee Meeeeeeee[‌88‌,‌88‌]

Me eeeeeeeee eeeeee M8-eeeeeeeee eeeeeee, eeeeeeeee eeeee ee eeeeee eeeeeeee eeeeeeeee eee ee eeeeeeee eee eeeeeeeeeeee eeeeeeee eee eee eeeeeeeeeeeeeeee eeeeeeeeee ee eeeeeeeee. Meee, eeeeeee eeeeeeeee ee eeeeeeeeeeeeeeeeeeeeeee eeee 88 eee eeeeeeeeee eeeeeeee eeee eeeeeeeeeeeeeee eeeeee ee 88°M eeeee eee eeeeeeeeeee eeeeeee eeeeeeeeeeeeee eeee 88% ee (Meeeee 88).[‌88‌]

Meeeee 88 Meeeeeeeeeeeeeee Meeeeeeeee ee ee Meeeeeee[‌88‌]

M eeeeee eeeeeeeeeeeeee eeeeeee eeeeeeee eeee M8-eeeeeeeeee-M8-[(8-eeeeeee-8-eeeeeeee)eeeeeeeee]eeeeeeeeee eee eeeeeeeeeeeeeeeee eeeeeeee eee eeeeeeeeeeeeeeee eeeeeeee ee eeeeeeeeeeeeee eeeeeee ee eeeeeeeee, eeeeeeeee eee eeeeeeeeeeeee eeeeeeeee eeeeee eeeeeeeeeeee ee eeee eeeeee eeeee eeeeeeeee eeee 8M eeeeeeeeeeee eeee (Meeeee 88).[‌88‌]

Meeeee 88 Meeeeeeeeeeeeeee Meeeeeee ee Meeeeeeeeeeeee Meeeeee ee Meeeeeeee[‌88‌]

Meeeee eeeeeeeee ee 8,8-eeeeeeee-8,8-eeeeeeeeeeeeeee eeee eeeeeeeeeeeeeeeee (8 eeeeeeeeeee) ee eeee eeeeeeeeeee eeeeeeeee (8,8-eeeeeeee-8,8-eeeeeeeeeeeeeeee)eee(eeeeeeee­eeeeeeee) (88), eeeee eeeeeeeee ee e eeeeeeeee eeeeeeeeeeeeee Meeee eeee eee eeeeeeee eeeeeeee eee eeeeeeeeee ee eeeeeeee eeeeeeeee eeeeee eeeeeeeeeeee eeeeeeee eee eee eeeeee eeeeeeeeeeeee eeeeeeeeee ee eee eeeeeeee eeeeee. Meee, eeeeeee eeeeeeeeeeee ee eeeee-8-eee eeee 88 (8.8 eeeeeeeeeee) ee eeeeeeeeeeeeeee eee eeeeeeeeee eeeeeeee eeee eeeeeeeeeeeeeeee ee 88°M eeeee eeeee-8-ee ee 88% eeeee (Meeeee 88). Me eeeee eeeeeeee, eeeeeee, eeeeeeeee ee eeeee-8-eee eeee eeeeeeeeeeeeeeee ee eee eeeeeeee ee eee eeeeeeeeeee eeeeeeeeeeeeee eeeeeee 88 (eeeeeeee eeee 8,8-eeeeeee eee eeeeeeeeeeeeeeeee) eeeee ­eeeeeee eeeeeeee eeeeeeeeee eeeeeee eeeee-8-ee ee eeee 8% eeeee. M eeeeeee eeeeeeee ee eeeeeeee ee eeeeeeeee ee eee eeeeeeeeeeee eeeeeeee.[‌88‌]

Meeeee 88 Meeeeeeee ee Meeee-8-eee eee Meeeeeeeeeee[‌88‌]

Mee eeeeee eeeeeeeeeeeee eeeeeeeeee eeeeeeee eee eeee eeeeeee ee eee Meeee eeee eeeeeeee eeeeeeeeee, eeeee eeeeeeeeeeeeee 88, ee eeeeeeeee eeee eeeeeeeeeeeeeeeeeeeee eee, eeeeeeeeeeee, eeeeee eeeeeeee eeeeeeeeeeeeee eeeeeeeeeeeeeeeee ee eeeeeeeee ee eeeeeeee ee eee eeeeeeee ee eeeee eeeeeee (Meeeee 88). Mee eeeeeeee eeeeeeeeeeeeeeee ee eeeeee eeeeeeeeee eeeee eeeeeeee(MM) eeeeeeee ee eeeeeeee.[‌88‌]

Meeeee 88 Meeeeeeeee ee Meeeeeeee[‌88‌]

Mee eeeeeeeeee 88 ee eeeeeee eeee ee ee eeeeeeeee eeeee eeeeeeee eeeeee ee eeeeeeee eeeeeeeee, eeeee eeeeee eeeeee eeeeeeee eeeeeeeeee eeee eeeeeeeee eeee eeeeeeee eeeeeeeeeeeee eeeeeee.[‌88‌] Mee eeeeeeeeeee ee eeeeeeeeeeee eeee 8 eeeeeeeeee ee eeeeeeeeee 88 eeeeeeee eeeee eeeeeeee ee 88°M eee 8eeeee ee eeeeeee 8-eeeeeeeeeeeee ee 88% eeeee (Meeeee 88). Meeeeee, eeeeeee 88 eeeeeeeeeeeee eeeeeee eee eeee ee eeeeeeeeee eeeee eeeeeee eeeeeeeeee, eee eeee eee ee eeeeee 88 (8 eeeeeeeeeee) eeeee eeee ee eee eeeeeeeeeee eeeeeee ee 88°M. Meee eeee eeeeeeeeeeee ee eeeeeeeeee eeeeeeeeee; ee ee eeeeeeee eeee eee eeeeeeeeee 88 ee eeeeeeee eeee eee eeeeeeee eeeee eeeeee ee ee eeeeeeeeeee eeeeeee eee 8:8 eeeeeeeeeeee eeeeeeeee 88 eee 88, eee 88 ee eeeeeee ee ee eeeeee eeeeeeeeeee ee eee ee e eeeeee eee-eeeeeeee eeeeeeeeee eeeee ee eeeeeee eee eeeeeeeeee eeeeeee.

Meeeee 88 Meeeeeeeee ee Meeeeeeee[‌88‌]

References


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