0000000000177630
AUTHOR
Dezsö Falábu
Melamine induced conformational change of ethyl resorcinarene in solid state
When ethyl resorcinarene (1) and melamine (2) are co-crystallised, all intramolecular hydrogen bonds keeping the resorcinarene in crown conformation are broken causing an unexpected conformational change to boat, and a highly ordered hydrogen bonded network is formed.
Complexation of Small Molecules by Open-Ended Resorcarene Hosts
[structure: see text] Sterically hindered tetraaminomethylated resorcarenes form inclusion complexes in CDCl(3) with acetonitrile and acetaldehyde, which are kinetically stable on the NMR time scale at 233 K.
Mannich Reactions with Amino Alcohols
The condensation of resorcarenes 1 with various amino alcohols and an excess of formaldehyde was studied. The tetrabenzoxazines 2a−e were found as the only products in the reaction with 6-aminohexan-1-ol, 4-aminobutan-1-ol, and 2-aminoethanol, while 3-aminopropan-1-ol forms the tetraoxazine 3 as the main product. In the case of aminoethanols substituted at the 2-position with alkyl groups, the tetraoxazolidines 4 are the preferred reaction products, while 1-methyl aminoethanol (1-amino-propan-2-ol) yields predominantly the tetrabenzoxazine 2f. The structures of all these compounds have been confirmed by NMR spectroscopy and additionally by single-crystal X-ray analysis in the case of 2a and…