Sugars deoxyiodo

Photolysis of deoxyiodo sugars is an effective method for forming the corresponding deoxy compounds (see Scheme 33) however, both... 

Scheme 33.—Proposed Mechanism for Photochemical Reaction of Deoxyiodo Sugars.

Table XXIII (Continued) Photochemical Reactions of Deoxyiodo Sugars... 

Carbohydrate oxetanes have been prepared from deoxyiodo sugars without die use of strongly alkaline reagents. Thus, treatment of 5-deoxy-5-iodo-l,2-0-isopropylidene-a-D-xylofuranose with silver fluoride in cold pyridine afforded 3,5-anhydro-l,2-0-isopropylidene-... 

A synthesis of chalcose has also been achieved by way of reduction of a deoxyiodo sugar [see N. K. Kochetkov and A. I. Usov, Tetrahedron Lett., 519 (1963)]. 

The original Rydon reagent [51], methyl triphenoxyphosphonium iodide [(PhO)3P+-Mel-], which was used extensively for the preparation of deoxyiodo sugars [52-54] and nucleosides [41,55-59] is still a reliable and efficient protocol. 

Unless otherwise noted, acetone was the solvent. b Yield of deoxyiodo-sugar derivative. 0 Yield of sodium sulfonate. Yield by determination of sodium iodide consumed. Free iodine liberated. / Acetonylacetone. Corrected for solubility of sodium sulfonate in acetone. A Acetic anhydride. Isobutyl methyl ketone. 

Deoxyiodo sugars. lodo sugars have been prepared by reaction of isolated hydroxyl groups with this combination of reagents to form alkoxyphosphonium iodides in one operation. When the salts are heated in toluene at 110°, iodo sugars are formed with inversion. A typical example is formulated in equation (I) for the reaction of l,2 5,6-diisopropylideneglucose. 

DEOXYIODO SUGARS Tetra-n-butyl-ammonium iodide. 

A mechanistic study of the photolysis of deoxyiodo-sugars has been carried out. With secondary iodides epimerization was shown to... 

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