Navigation

0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via
20.2.1.8.15.10.3 Conjugate Addition of Heteroatoms

DOI: 10.1055/sos-SD-120-00214

Sawamura, M.; Shimizu, Y.Science of Synthesis Knowledge Updatesearly view.

Conjugate addition of nitrogen-based nucleophiles is feasible with the aid of boron catalysts.[‌68‌‌72‌] Specifically, the integrated chiral boron compound 58, comprising a boronic acid and a thiourea moiety, is a powerful catalyst for the conjugate addition of O-benzylhydroxylamine to α,β-unsaturated carboxylic acids to afford β-amino acid derivatives 59 (after conversion into the corresponding methyl ester) with high enantioselectivities (Scheme 31).[‌70‌‌72‌] The addition of benzoic acid improves enantioselectivities.

Meeeee 88 Meeeeeeee Meeeeeee ee M-Meeeeeeeeeeeeeeeeee ee α,β-Meeeeeeeeee Meeeeeeeee Meeee[‌88‌]

Meeeeeeeeee 88

M8 ee (%) Meeee (%) ee 88 Mee
(MM8)8Me 88 88 [‌88‌]
Me 88 88 [‌88‌]
eMe 88 88 [‌88‌]
MM8 88 88 [‌88‌]
(MM8)8MMMee 88 88 [‌88‌]

Mee eeeeeeee eeeeeee eeee eeeeeeeee 88 eee 88 eeee eeeeeee eeeeeeeeee eeeeeeeee eeeeeeee ee eeeeeeeeeeeee ee α,β-eeeeeeeeeee eeeeeeeeee eeeee (eeeeeeee ee eee eeeeeeeeeeeee eeeeee eeeeee 88) (Meeeee 88).[‌88‌] Meeeeeeeeeeee, eee eeeeeeee eeeeeeeeeeeeeee ee eee 8-(eeeeeeeeeeee)eeeeeeee eeee eeeeeeee eee ee eeeeeeeeee ee eeeeeeeee ee eee eeeeeee: (M)-8-(eeeeeeeeeeee)eeeeeeee eeeee eee eeeeeeee ee eeeeee eeeeeeeeeeeee eeeeeee eee M-eeeeeeee eee eeeeee ee eeeeeee. Mee eeeeee eee eeeeeeeeeeeeeeeeeeee eee eeeeeeeee eeee eee eeee eeeeeee eeeeeeeeee.

Meeeee 88 Meeeeeeee Meeeeeee ee Meeeee ee α,β-Meeeeeeeeee Meeeeeeeee Meeee[‌88‌]

Meeeeeeeeee 88

M8 Me8 Meeeeeee Meeeeee ee (%) Meeee (%) ee 88 Mee
Me Me 88 MMe8 88 88 [‌88‌]
Me Me 88 eeeeeee 88e 88 [‌88‌]
MM8MMe 8-MeMM8M8 88 MMe8 88 88 [‌88‌]
MM8MMe 8-MeMM8M8 88 eeeeeee 88e 88 [‌88‌]
Me 8-MeM8M8 88 MMe8 88 88 [‌88‌]
Me 8-MeM8M8 88 eeeeeee 88e 88 [‌88‌]

e Mee eeeeeeee eeeeeeeeee ee eee eeeeeee eee eeeeeeee.

Meeeeeeeeeee Meeeeeeee

Meeeee (M)-8-[(Meeeeeeee)eeeee]eeeeeeeeee 88; Meeeeee Meeeeeeee:[‌88‌]

M eeee ee M-eeeeeeeeeeeeeeeeeee (8.88 eeee) ee eeeeeeeeeeeeeeeee (8.88 eM) eee eeeee ee ee ee e eeeeeee eeeeeeeeee ee ee α,β-eeeeeeeeeee eeeeeeeeee eeee (8.88 eeee), eeeeeee eeee eeeeeeee 88 (88 eee%), eeeeeee eeee (8.88 eeee, 8 eeeee), eee eeeeeeeee 8-Å eeeeeeeee eeeeee (88 ee) ee eeeeeeeeeeeeeeeee (8.88 eM). Mee eeeeeee eee eeeeeee ee ee eee 88 e eee eeee eeeeeeee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/MeMMe) ee eeeeee eee eeeee eeeeeee.

Me eee eeee ee eee eeeee eeeeeee ee eeeeeee/MeMM (8:8; 8 eM) eee eeeeee eeeee e 8.8 M eeee ee MMMMMM8 ee Me8M (8.88 eM, 8.8 eeee) ee 8°M. Mee eeeeeeeee eeeeeee eee eeeeeee ee 8°M eee 88 eee eee eeee eeeeeeee eeee MeMM eeeee eee eeeeee eeeee ee eee eeee eeeeeeeeeee. Mee eeeeeee eee eeeeeeeeeeee eee eee eeeeeee eee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/MeMMe).

Meeeeeeeeeeeeee Meeeee 8-(Meeeeeeeeeee)eeeeeeeeee 88; Meeeeee Meeeeeeee:[‌88‌]

M eeee ee e eeeeeeeeeeee (8.88 eeee) ee MMe8 (MMMMMMM: eeeee) ee eeeeeee eee eeeee ee ee ee e eeeeeee eeeeeeeeee ee ee α,β-eeeeeeeeeee eeeeeeeeee eeee (8.88 eeee), eeeeeee eeee eeeeeeee 88 ee 88 (88 eee%), eee eeeeeeeee 8-Å eeeeeeeee eeeeee (88 ee eee MMe8, 888 ee eee eeeeeee) ee MMe8 (88 µM eeeee eeeeee) ee eeeeeee (8.8 eM eeeee eeeeee). Mee eeeeeee eee eeeeeee ee ee eee 88 e eee eeee eeeeeeee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/MeMMe ee MeMMe/MeMM) ee eeeeee eee eeeee eeeeeeeeee eeee eeeeeee.

M 8.8 M eeee ee MMMMMM8 ee Me8M (8.88 eM, 8.8 eeee) eee eeeeee eeeee ee 8°M ee e eeee ee eee eeeee eeeeeeeeee eeee ee eeeeeee/MeMM (8:8; 8 eM). Mee eeeeeeeee eeeeeee eee eeeeeee ee 8°M eee 88 eee eee eeee eeeeeeee eeee MeMM eeeee eee eeeeee eeeee ee eee eeee eeeeeeeeeee. Mee eeeeeee eee eeeeeeeeeeee eee eee eeeeeee eee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/MeMMe) ee eeeeee eee eeeeeeeeeeeee eeeeee eeeee 88.

References


Cookie-Einstellungen