2-Alkenoyl pyridine N-oxides are introduced as a new kind of efficient dienophiles for the Cu(II)-bis(oxazoline) (BOX) catalyzed enantioselective Diels-Alder reaction affording higher reactivity and enantioselectivity (ee's up to 96%) than the corresponding nonoxidized 2-alkenoyl pyridines.

Aryl boronic acids and esters are important building blocks in API synthesis. The palladium-catalyzed Suzuki-Miyaura borylation is the most common method for their preparation. This paper describes an improvement of the current reaction conditions. By using lipophilic bases such as potassium 2-ethyl hexanoate, the borylation reaction could be achieved at 35 °C in less than 2 h with very low palladium loading (0.5 mol %). A preliminary mechanistic study shows a hitherto unrecognized inhibitory effect by the carboxylate anion on the catalytic cycle, whereas 2-ethyl hexanoate minimizes this inhibitory effect. This improved methodology enables borylation of a wide range of substrates under mild conditions.

The unexpected ability of arylzinc reagents bearing electron-donating substituents to react in a Friedel-Crafts fashion (cine) with electrophiles like perpivaloylated glucoside bromide and benzhydryl bromides in competition with organometallic coupling (ipso) is shown. The stereoelectronic factors required to promote the cine reactivity versus the classical ipso, and the mechanism of this alternative pathway, have been investigated. The Wheland intermediate is deprotonated intramolecularly in a 1,2-shift but also in a longer-range shift, leaving in this case the C-Zn untouched. In the latter case, it is possible to take advantage of this result for further functionalization.

A general catalytic inverse electron demand hetero-Diels Alder reaction for 2-alkenoylpyridine N-oxides is presented. 2-Alkenoylpyridine N-oxides react very efficiently with alkenes in the presence of bisoxazolidine-copper(II) [BOXCu(II)] complexes to give chiral dihydropyrans bearing a pyridine ring at the 6-position with very high yields and excellent diastereo-and enantioselectivity. These heterodienes exhibited higher reactivity and enantioselectivity than the corresponding non-oxidized 2-alkenoylpyridines.

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Enantioselective nitrone cycloadditions with 2-alkenoyl pyridine N-oxides as dipolarophiles have been reported. The reaction is catalyzed by Cu(II)-BOX complexes to give the expected isoxazolidine products with high diastereo- and enantioselectivity.

Complex: The synthesis of the glycolipid PGL‐tb1 present in the outer membrane of hypervirulent strains of Mycobacterium tuberculosis has been accomplished for the first time by using a highly convergent strategy featuring a Sonogashira coupling to unite a phenolic trisaccharide with the phthiocerol. Efficient asymmetric Cu‐catalyzed 1,4‐additions to unsaturated thioesters and cyclic enones have been employed to introduce the methyl groups.

An easy access to substituted (R)-3-hydroxy-3-phenyloxindoles, (R)-benzylic acids, and benzophenones is described. The reaction of the lithium enolate of the (2S,5S)-cis-1,3-dioxolan-4-one derived from optically active (S)-mandelic acid and pivalaldehyde with several o- and p-halonitrobenzenes proceeds readily to give the corresponding arylation products in good yields and diastereoselectivities. The reduction of the nitro group with Zn/HCl/EtOH in the o-nitro arylation products with concomitant intramolecular aminolysis of the dioxolanone moiety leads directly to enantiomerically pure (R)-3-hydroxy-3-phenyloxindoles. On the other hand the basic hydrolysis of the dioxolanone moiety in all the arylation products (ortho and para) leads to enantiomerically pure substituted (R)-benzylic acids. The oxidative decarboxylation of these latter with oxygen as terminal oxidant in the presence of pivalaldehyde and the Co(III)-Me2opba complex as catalyst gives substituted nitrobenzophenones.