ISSN:
1573-1111
Keywords:
Chiral crown ethers
;
glycopyranosides
;
mannitol derivatives
;
borane ammonia complexes
;
crystal structures
;
enantioselective reductions
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Whereas 1 ∶ 1 crystalline complexes have been isolated between borane ammonia and methyl 4,6-O-benzylidene-2,3-dideoxy-α-d-galactopyranosido [2,3-b]-1,4,7,10,13,16-hexaoxacyclo-octadecane (1), methyl 4,6-O-benzylidene-2,3-dideoxy-α-d-mannopyranosido [2,3-b] (methyl 4′,6′-O-benzylidene-2′,3′-dideoxy-α-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-α-d-mannopyranosido[2,3-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.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00655736
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