Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

• Susan Kelleher,
• Pierre-Yves Quesne and
• Paul Evans

Beilstein J. Org. Chem. 2009, 5, No. 69, doi:10.3762/bjoc.5.69

• carbocation rearrangement takes place faster than any nucleophilic interception of species 21 and 22. (A hydride shift from the bridging CH2 to carbocation 21 was also considered; however, based on the regioselective formation of compound 19b this mechanism was discounted.) The remarkable contrasting

The tert- amino effect in heterocyclic chemistry: Synthesis of new fused pyrazolinoquinolizine and 1,4-oxazinopyrazoline derivatives

• Dipak Prajapati and
• Kalyan Jyoti Borah

Beilstein J. Org. Chem. 2007, 3, No. 43, doi:10.1186/1860-5397-3-43

• undergoing a 1,5-(4 → 5) hydride shift prior to cyclization to yield a 6-membered ring product 6 (Scheme 2). This is in contrast to an earlier report by Sandhu et al to obtain pyrrolo [2,3-d]pyrimidines from 6-tert-amino-substituted uracils and dimethyl acetylenedicarboxylate.[32] However, further work is in