Reactions of emamines. X. Methylene bases in the benzothiazole series as enamines

N‐Heterocyclic Carbene Catalyzed Umpolung of Michael Acceptors for Intermolecular Reactions

“…[14] Intermediate 10 bears a strong resemblance to the Breslow intermediate, [15] which is usually formed by the addition of an NHC to aldehydes and is nucleophilic at the b-carbon atom (umpolung). This deoxy Breslow intermediate [16] 10 adds to another molecule of 1 to form the ester enolate 11, which undergoes proton transfer and elimination of the NHC to form the observed product 2.…”

On new N-heterocyclic carbene derived alkylidene imidazolines

“…Based upon literature precedents by Kuhn, 12,17a,b, 22 Bourson, 23 Begtrup, 13a,24 and Alt 25 we set out to probe the nucleophilicity of enediamines 4 and 5 in selected reactions with electrophiles. We observed protonation of benzylidene 4 at the exocyclic acarbon.…”

Palladium‐Catalyzed Direct Arylation of Aryl(azaaryl)methanes with Aryl Halides Providing Triarylmethanes.

“…NMR (CDCl 3 ) δ 5.78 (s, 2H), 7.12 (dd, J = 7.5, 5.0 Hz, 4H), 7.21 (s, 4H), 7.24 (d, J = 7.5 Hz, 4H), 7.60 (dd, J = 7.5, 7.5 Hz, 4H), 8.56 (d, J = 5.0 Hz, 4H); 13 C NMR (CDCl 3 ) δ 61. 6,121.7,124.3,129.6,136.6,140.3,149.6,162.3. Found: C,81.00;H,5.23…”

“…Effect of Base Screening of Ligand IR (neat) 699, 746, 1419, 1496, 1561, 3032 cm -1 ; 1 H NMR (CDCl 3 ) δ 4.30 (s, 2H), 7.12 (dd, J = 5.0, 5.0 Hz, 1H), 7.21-7.24 (m, 1H), 7.29-7.32 (m, 2H), 7.36-7.37 (m, 2H), 8.68 (d, J = 5.0 Hz, 2H);13 C NMR (CDCl 3 ) δ 46.2, 118.8, 126.8, 128.7, 129.3, 138.3, 157.5, 170.2. Found: C, 77.87; H,6.02; N, 16.37%. Calcd for C 11 H 10 N 2 : C, 77.62; H, 5.92; N, 16.46%.…”