Abstract: | Whereas 1 1 crystalline complexes have been isolated between borane ammonia and methyl 4,6-O-benzylidene-2,3-dideoxy--d-galactopyranosido 2,3-b]-1,4,7,10,13,16-hexaoxacyclo-octadecane (1), methyl 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido 2,3-b] (methyl 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido 2,3-k]-1,4,7,10,13,16-hexaoxacyclo-octadecane (3), and (1R,2R,7R,24R)-3,5,8,11,14,17,20,23,26,28-decaoxatricyclo-21.4.0.02,7]octacosane (4), the hosts, methyl, 4,6-O-benzylidene-2,3-dideoxy--d-mannopyranosido2,3-b] 1,4,7,10,13,16-hexaoxacyclo-octadecane (2) and 1,4 1,4 3,6 3,6-tetra-anhydro-2,2 5,5-bis-O-oxydiethylenedi-d-mannitol (5) have yielded 2 1 (guest:host) crystalline complexes with borane ammonia as guest. X-ray analyses of the supramolecular structures of BH3NH3 ·1, (BH3NH3)2 ·2, BH3NH3 ·3, BH3NH3 ·4, and (BH3NH3)2 ·5 have been carried out and BH3NH3 ·1, BH3NH3 ·2, and (BH3NH3)2 ·5 have been shown to reduce acetophenone with enantiomeric excesses of 5, 13, and 10% respectively.
Supplementary Data relating to this article (atomic coordinates of the hydrogen atoms and thermal parameters) are deposited with the British Library as Supplementary Publication No. SUP 82017 (74 pages).Dedicated to Professor H. M. Powell. |