Use of bis-(aminol) ethers derived from N-(S)-(−)-α-methylbenzylamine in reactions with resorcinarenes and double Mannich reactions

The synthesis of some chiral bis-(aminol)ethers are described. Reaction of a solution of the resorcin[4]arene derived from propanal with N,N-bis(methoxymethyl)-N-(S)-(−)-α-methylbenzylamine in toluene at 85 °C initially afforded a 1:1 mixture of two diastereoisomeric tetrakis(benzoxazines). Further, heating of this mixture under reflux in ethanol for 24 h afforded the crystalline (αS),(S)-diastereoisomer in 77% yield. N,N-bis(ethoxymethyl)-N-(S)-(−)-α-methylbenzylamine and N,N-bis(ethoxymethyl)-N-(R)-(+)-α-methylbenzylamine were reacted with β keto esters to afford a 1:1 mixture of the diastereoisomeric double Mannich adducts. Two of the double Mannich adducts were converted into tricyclic ABE analogues of the alkaloid methyllycaconitine .