A new approach to the synthesis of benzylidene derivatives of 1-(α-aminobenzyl)-2-naphthols (Betti bases), promising chiral inductors

Synthesis of 1‐(α‐Aminobenzyl)‐2‐naphthol Derivatives, their Structure in Crystal and in Solution

“…Recently, we reported a new approach to the synthesis of 1,3‐diaryl‐2,3‐dihydro‐1 Н ‐naphtho[1,2‐е]oxazines – Betti base derivatives. The method involves the interaction of 2‐naphthol 1 with very accessible 1,3,5‐trisaryl‐2,4‐diazapenta‐1,4‐dienes 2 in molar ratio 3:2 in boiling benzene (Scheme ) .…”

“…Recently, we reported a new approach to the synthesis of 1,3‐diaryl‐2,3‐dihydro‐1 Н ‐naphtho[1,2‐е]oxazines – Betti base derivatives. The method involves the interaction of 2‐naphthol 1 with very accessible 1,3,5‐trisaryl‐2,4‐diazapenta‐1,4‐dienes 2 in molar ratio 3:2 in boiling benzene (Scheme ) . To expand the boundaries of proposed method, 6‐bromo‐2‐naphthol was used in the reaction with 1,3,5‐trisaryl‐2,4‐diazapenta‐1,4‐dienes 2c , 2d , 2e , 2f resulting in formation of 3g , 3h , 3i , 3j with good yield and purity.…”

“…1,3,5‐Trisaryl‐2,4‐diazapenta‐1,4‐dienes 2a , 2b , 2c , 2d , 2e , 2f were prepared according to the known method . 1,3‐diarylnaphthoxazines 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j were obtained by interaction of 2‐naphthols 1 with 1,3,5‐trisaryl‐2,4‐diazapenta‐1,4‐dienes 2 following the method . Tautomeric ratio ( A , B , and C ) for compounds 3g , 3h , 3i , 3j was determined by integration of proton signals in 1 Н NMR spectra and given in Table .…”

Chiral Thiophosphorylated Thioureas: Synthesis, Structure, and Cyclization Reaction

“…For the synthesis of chiral thiophosphorylated thioureas, the addition reaction of chiral amines to O , O ‐diethyl thiophosphoryl isothiocyanate was chosen as the most convenient and efficient procedure. As an amine part, we have used commercially available 2‐aminobutan‐1‐ol and 1‐(α‐aminobenzyl)‐2‐naphthol (Betti base), which was synthesized in racemic and in enantiopure forms according to various workers . It should be noted that in recent years the Betti bases attracted great interest of researchers as a chiral platform for various purposes , including the stereoselective synthesis of organophosphorus compounds .…”

Stereoselective Synthesis of α-Aminophosphonic Acids Using the Betti Base as Chiral Auxiliary

“…8 The method involves the reaction of β-naphthol with 1,3,5-triaryl-2,4-diazapenta-1,4-dienes 5a-e in a molar ratio of 3:2 in refluxing benzene (Scheme 2). All products (X = H, OMe, Br, Cl, NMe 2 ) were obtained in yields from 88% to nearly quantitative as crystalline compounds after the reaction mixture was cooled or the solvent was removed.…”