Some Reactions of Methylene-Bis-Amines as Ammono-Aldehydes

Lewis Acid Catalyzed Condensation–Cyclization Cascade: Direct Synthesis of Di/Trifluoromethyl‐1,2,3,4‐tetrahydroquinazolines

“…KMnO 4 or MnO 2 are commonly used for similar reactions. [21,22] We found that all tetrahydroquinazolinep roducts obtained could be oxidized to the corresponding dihydro derivative using MnO 2 as the oxidant. When we conducted the reaction directly with the crude reaction mixture obtained after condensation-cyclization, the reaction was not successful possibly due to the presence of Ga(OTf) 3 .…”

Synthesis of 3′-Aminopteroic Acid

“…Another possibility for the production of an antimetabolite from 11 is that 1oN-hydroxymethyl-3'-aminotetrahydrofolic acid which might be formed through the serine-glycine interchange (5) may condense intrainolecularly to form IVY since N-hydroxyTv methylamines have a tendency to combine with another ligand (6). Compound 1V could then be a competitive inhibitor of 'ON-hydroxymethyltetrahydrofolic acid by blocking the active site of cyclohydrolase (2).…”

THE COURSE OF THE MANNICH REACTION1

“…The existence of ion X cannot be demonstrated experimentally, but assumption of such an intermediate has permitted rationalization of a number of superficially diverse acid-induced reactions of aldehydes with primary or secondary amines, or of corresponding methylene-bis-amines or Schiff bases previously studied in this laboratory (6,13,14,15). The existence of ion X cannot be demonstrated experimentally, but assumption of such an intermediate has permitted rationalization of a number of superficially diverse acid-induced reactions of aldehydes with primary or secondary amines, or of corresponding methylene-bis-amines or Schiff bases previously studied in this laboratory (6,13,14,15).…”

“…If I11 is frankly acidic (e.g., a phenol) it can participate in Mannich reactions under mild conditions and in absence of added acid (6) or even in presence of alkali in small amount (4). If I11 is frankly acidic (e.g., a phenol) it can participate in Mannich reactions under mild conditions and in absence of added acid (6) or even in presence of alkali in small amount (4).…”

“…0 I I // 1 1 \ 6 Mannich bases of the type RNHC-C-C , retaining a reactive hydrogen, are nitro-R gen system analogs of diacetone alcohol and may form reversibly. The carbon-carbon bonds established in the 5 Methylene-bis-arylamines, and also Schiff bases derived from arylamines, may not persist offing t o secondary reactions.…”