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Lithium mesitylmethyl(trimethylsilyl)amide behaved as a nice amination agent in a chiral ligand-controlled conjugate addition reaction of tert-butyl cinnamate to give the conjugate amination product with 99% ee in 90% yield. Other acyclic and cyclic enoates were also aminated in reasonably high enantioselectivity, while the deprotonation of abstractable proton of enoates caused yield loss of the conjugate amination products, due to the bulkiness and enriched basicity of the lithium amide. Although such steric bulkiness made hard the hydrogenolytic cleavage of a mesitylmethyl–N bond of the adducts, a new protocol comprising N-chlorination–regioselective dehydrochlorination–transoximation was developed for N-dearylmethylation, giving 3-aminoalkanoates in reasonably good yields.

A simple method for the direct synthesis of 2,2′-binaphthols 2 and dinaphtho[1,2-b;2′,1′-d]furans 3 under mild conditions was developed, utilizing a biaryl coupling reaction via electron donor–acceptor complexes of 1-naphthols with SnCl4. Heating of the complex in a sealed tube for (18–24 h) afforded the corresponding o–o coupled product 2 in excellent yield. Prolonged reaction (56–65 h) under the same conditions afforded 3 in high yield in one step. We also found that in the case of α-naphthol without substituents other than a hydroxyl group at the C-1 position, regioselective o–o coupling reaction proceeded. The products 2a, 2b and 2g should be useful as synthetic intermediates for naturally occurring 3,3′-bijuglone, 3,3′-biplumbagin and elliptinone.

Systematic structure tuning of lithium amides derived from benzyl- N -TMS-, allyl- N -TBDMS-, and diisopropylamines lead to several candidates including anthracen-9-ylmethanamine which provided high performance in the enantioselective 1,4-addition (91% ee) and following hydrogenolysis with 10% Pd/C-H 2 in methanol to afford β-amino ester.

A simple method for the direct synthesis of 2,2′-binaphthols was developed, utilizing aryl–aryl coupling reaction via electron donor–acceptor complexes of 1-naphthols with SnCl 4 . Heating of the complex in a sealed tube afforded the corresponding o - o coupling product in excellent yield. This method was utilized for a biomimetic synthesis of the binaphthoquinone, 3,3′-biplumbagin, isolated from Plumbago zeylanica .