Details

Autor(en) / Beteiligte

• Jacintomoreno, Anwar
• Sharma, Hemant K.
• Metta‐Magaña, Alejandro
• Pannell, Keith H.

Titel

Aminomethyl Transfer (Mannich) Reactions Between an O‐Triethylsilylated Hemiaminal and Anilines, RnC6H5−nNH2 Leading to New Diamines, Triamines, Imines, or 1,3,5‐Triazines Dependent upon Substituent R

Ist Teil von

• Chemistry : a European journal, 2019-08, Vol.25 (48), p.11302-11307

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2019

Quelle

Wiley Online Library

Beschreibungen/Notizen

• The reactions of the Mannich reagent Et3SiOCH2NMe2 (1) with a variety of anilines (mono‐substituted RC6H4NH2, R=H, 4‐CN, 4‐NO2, 4‐Ph, 4‐Me, 4‐MeO, 4‐Me2N; di‐substituted R2C6H3NH2, R2=3,5‐(CH3)2, 3,5‐(CF3)2; tri‐substituted R3C6H2NH2, R3=3,5‐Me2‐4‐Br and a “super bulky” aniline (Ar*NH2) [Ar*=2,6‐bis(diphenylmethyl)‐4‐tert‐butylphenyl]) led to the formation of a range of products dependent upon the substituent. With electron‐withdrawing substituents, previously unknown diamines, RC6H4NH(CH2NMe2) [R=CN (2 a), NO2 (2 b)] and R2C6H3NH(CH2NMe2) [R2=3,5‐(CF3)2 (2 c)] were formed. Further reaction of 2 a, b, c with 1 yielded the corresponding triamines RC6H4N(CH2NMe2)2 (R=CN (3 a), NO2 (3 b) and R2C6H3N(CH2NMe2)2, R2=3,5‐(CF3)2 (3 c). The new polyamines were characterized by NMR spectroscopy, and for 2 a, 2 c, and 3 c, by single crystal XRD. In the case of electron‐donating groups, R=4‐OMe, 4‐NMe2, 4‐Me, 3,5‐Me2, 3,5‐Me2‐4‐Br, and for R=4‐Ph, the reactions with 1 immediately led to the formation of the related 1,3,5‐triazines, R=4‐MeO (5 a), 4‐Me2N (5 b), 4‐Me (5 c), 3,5‐Me2 (5 d), 3,5‐Me2‐4‐Br (5 e), 4‐Ph (5 f), 4‐Cl (5 g). The “super bulky” aniline rapidly produced a single product, namely the corresponding imine Ar*N=CH2 (4) which was also characterized by single crystal XRD. Imine 4 is both thermally and oxidatively stable. All reactions are very fast, thus based upon the presence of Si we are tempted to denote the reactions of 1 as examples of “Silick” chemistry. The reactions of the Mannich reagent Et3SiOCH2NMe2 with a variety of anilines (mono‐substituted RC6H4NH2, R=H, 4‐CN, 4‐NO2, 4‐Ph, 4‐Me, 4‐MeO, 4‐Me2N; R2C6H3NH2; di‐substituted R2=3,5‐(CH3)2, 3,5‐(CF3)2; R3C6H2NH2; tri‐substituted R3=3,5‐Me2‐4‐Br; and a “super bulky” aniline (Ar*NH2) [Ar*=2,6‐bis(diphenylmethyl)‐4‐tert‐butylphenyl]) have been investigated. These led to the formation of di‐ and triamines, as well as 1,3,5‐triazines, or imines, depending on the substituent.