Enantioselective conjugate addition of organometallic reagents to α,β-unsaturated organic substrates is among the most important of organic transformations1,2. Substrates used in this reaction are usually α,β-unsaturated ketones, aldehydes, esters, amides, sulfoxides, or nitro compounds. Often referred to as 1,4-addition, these reactions use a variety of organometallic reagents, where non-stabilized organic moieties are directly introduced into an organic structure with high chemo- and regioselectivity transforming sp2 carbon into an sp3 one 1.
Since asymmetric synthesis plays a key role in chiral ligands, Strem is happy to introduce two new BINAP-based phosphoramidite products 15-0860 and 15-0870, that have been developed at the University of Oxford (Fig. 1).
Fig. 1. New Phosphoramidite Ligands
Using phosphoramidite ligands; 15-0860 and 15-0870, as the catalytic source of chirality, positive activity in the copper-catalyzed hydrometalation/asymmetric conjugate addition approach of alkylzirconium reagents has been reported, which provides all-carbon quaternary centers by coupling alkenes with β-substituted enones3-6 and α,β-unsaturated lactones7. More details are given in the corresponding technical notes found on our web site at www.strem.com.
References:
Newphosphoramidite ligands:
15-0860: (11bS)-N-(Diphenylmethyl)-N-(i-propyl)dinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepin-4-amine (1637749-69-9)
15-0870: (11bS)-N-((R)-2,3-dihydro-1H-inden-1-yl)-N-(di-n-butylmethyl)dinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepin-4-amine
Related Resources & Product Lines:
Ligands & Chiral Ligands
MONOPHOS Product Family
Phosphine Product Family
Phosphine Ligands
Phosphorus Ligands and Compounds Booklet
Other Ligands Booklet