Science of Synthesis

Bingham, M. J.; Greaney, M. F., Science of Synthesis, (2008) 36, 995.

The three-component coupling of boronic acids ‌44‌, aldehydes ‌45‌, and amines ‌46‌ is a powerful approach to the synthesis of functionalized amines ‌47‌ (‌Scheme 19‌). The reaction, introduced by Petasis in 1997, is usually carried out with glyoxylic or α-hydroxy aldehyde components that contain a coordinating functional group adjacent to the carbonyl group.[‌151‌,‌152‌] This method produces the product subclass in a single simple step, and many of the starting materials are commercially available. In addition, the reaction is highly diastereoselective for anti-β-amino alcohols (e.g., ‌48‌) and, in cases where the α-hydroxy aldehyde is employed as a single enantiomer, proceeds without detectable racemization to produce optically pure products.

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‌Meeeeeeeeee 88‌

M8	M8	Meeee ‌88‌	Meeeeee	Meeee (%)	Mee
8-eeeee	MM8	MeMMMe		88	[‌888‌]
8-MeMM8M8	Me	Me8MM		88	[‌888‌]
M-MM=MMMe	MM8MM	MeMMMe		88	[‌888‌]
M-MM=MMMe	Me (M)	MM8		88e	[‌888‌]
	Me (M)	M-eeeeeeeeeeeee		88e	[‌888‌]
M-MM=MMMe	Me	Me8MM		88	[‌888‌]

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Meeeeeeeeeee Meeeeeeee

eeee-(8M)-8-(Meeeeeeeeeeee)-8-eeeeeeeeee-8-ee-8-ee (‌88‌); Meeeeee Meeeeeeee:[‌888‌]

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References