ISSN:
0009-2940
Keywords:
Carbene complexes of carbohydrate derivatives
;
Vinylcarbene chromium and tungsten complexes
;
α-D-Mannofuranosides, 2,3:5,6-di-O-isopropylidene-, of carbene complexes
;
α-D-Allofuranosides, 1,2:5,6-di-O-isopropylidene-, of carbene complexes
;
α-D-Glucofuranosides, 1,2:5,6-di-O-isopropylidene-, of carbene complexes
;
1,2-Propadienyliden tungsten complex
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Organic Syntheses via Transition Metal Complexes, 62. - First Carbene Complexes (M=Cr, W) with Carbohydrate SubstituentsThe first examples of transition metal carbene complexes of carbohydrate derivatives are described: 1,2:5,6-Di-O-isopropyliden-α-D-glucofuranose (2a), 1,2:5,6-di-O-isopropylidene-α-D-allofuranose (2b), and 2,3:5,6-di-O-isopropyliden-α-D-mannofuranose (2c) add regiospecifically at C-3 of alkynylcarbene complexes LnM=C(OEt)-C≡CPh 1 [LnM=Cr(CO)5 (a), W(CO)5 (b)] to give vinylcarbene complexes LnM=C(OEt)-CH=C(Ph)-O(sugar) (E/Z)-3a-g in good to excellent yields. As a minor side reaction the alkynyl carbene complex (CO)5W=C(OEt)-C≡CPh (1b) isomerises to give the 1,2-propadienylidene complex (CO)5W=C=C=C(OEt)C6H5 (4b).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19921251224
