Inherently chiral calix[4]arenes via oxazoline directed ortholithiation: synthesis and probe of chiral space

• Simon A. Herbert,
• Laura J. van Laeren,
• Dominic C. Castell and
• Gareth E. Arnott

Beilstein J. Org. Chem. 2014, 10, 2751–2755, doi:10.3762/bjoc.10.291

• File 1 for full details). Over the course of this work we have found that the lithiations are best performed at −78 °C and at a concentration of 0.15 M with either 5 or 6 equivalents of alkyllithium. Higher temperatures unsurprisingly resulted in poorer diastereoselectivity, pointing to kinetic control

Carbamate-directed benzylic lithiation for the diastereo- and enantioselective synthesis of diaryl ether atropisomers

• Abigail Page and
• Jonathan Clayden

Beilstein J. Org. Chem. 2011, 7, 1327–1333, doi:10.3762/bjoc.7.156

• turned out to be impossible to establish unequivocally the relative or absolute stereochemistry of the products obtained from the lithiations. However, we can make several important conclusions from this work. Firstly, racemisation of the intermediate organolithiums is demonstrably slow, because an

Selectivity in C-alkylation of dianions of protected 6-methyluridine

• Ngoc Hoa Nguyen,
• Christophe Len,
• Anne-Sophie Castanet and
• Jacques Mortier

Beilstein J. Org. Chem. 2011, 7, 1228–1233, doi:10.3762/bjoc.7.143

• halides do not alkylate 6-lithiouridine, compounds 3 were prepared in a regioselective manner by sequential treatment of 6-methyluridine 2 with LTMP or LDA (4 equiv) in THF at −30 °C followed by alkylation with ω-alkenyl bromides. Keywords: C6-alkylation; cyclonucleosides; lithiations; 6-ω

• Li2CuCl4 [16][17][18] to 11 followed by quenching with 4-bromobut-1-ene failed to produce 3a. Consequently, lateral lithiations were examined. Lateral lithiation of benzenoid aromatics requires a stabilizing group capable of either delocalizing negative charge or stabilizing an organolithium by

• inhibitors of anti-apoptotic Bcl-2 family proteins [28]. Literature furnishes little information regarding lateral lithiations in the nucleoside field and the data, scarce as they are, even appear to be inconsistent at first sight. Treatment of 2',3',5'-tri-O-benzoyl-3,6-dimethyluridine (13) with