Mannitol 1.6- ditosylate

Since no other stereoisomer but that of iditol, mannitol or sorbitol can exist in the as-fused ring series of l,4 3,6-dianhydrohexitols and since amination experiments on the ditosyl derivatives of each isomer have given three different amino derivatives, it is reasonable to assume that the two diamines which have been isolated are of the same configuration as their parent dianhydrohexitols. These two diamines LXXIV and LXXV on treatment with nitrous acid suffered deamination as expected but instead of obtaining in one case isomannide and in the other isosorbide, only one dianhydrohexitol was isolated and that was dian-hydro-L-iditol. The deamination must of course lead to the transitory carbonium cation LXXVIII and this on hydroxylation can take on any of the configurations, L-iditol, D-mannitol or D-sorbitol. That it preferentially takes on the configuration of L-iditol indicates that this is in some ways a more stable structure than the others. This behavior is paralleled... 

A base-promoted (2 -t- 2) cyclization between l,2 5,6-di-0-isopropylidene-D-mannitol (Figure Ab) and diethylene glycol ditosylate had previously been applied (88, 106, 107) successfully to the preparation of the chiral 18-crown-6 derivative dd-27 (p. 228), whence dd-28 to dd-30 can be obtained. However,... 

Normally, however, the reaction involving the formation of hydroxy-methylfurfural proceeds less readily than does the hydrogenation of glucose and fructose to mannitol and sorbitol, but its occurrence is detected by the fact that tetrahydrofuran derivatives have been isolated from the hydrogenation products. Thus, we have isolated tetrahydrofuran 2,5-dicarbinol (identified as its ditosyl derivative), 5-methyltetra-hydrofurfuryl alcohol and 2,5-dimethyltetrahydrofuran (VII) together with hydrogenolysis products of these compounds. 

When the methylenation of D-mannitol is carried out at a higher temperature and for a shorter time, there is produced a dimethylene-D-mannitol (m. p. 204-208°), in addition to the triacetal previously mentioned.68 The dimethylene compound is not oxidized by periodic acid and its ditosyl ester does not exchange with sodium iodide, even in acetic anhydride at 140°.62 Consequently it must be either 1,2,4,6- or 1,3,4,6-dimethylene-D-mannitol (the 1,2,4,6- and 1,3,5,6-structures are identical) the 1,3 4,6-structure was favored by Ness, Hann and Hudson40 in view of the rapidity of its conversion into 1,3 2,5 4,6-trimethylene-D-mannitol. 

Muller converted D-mannitol into the 1,6-diiodide as follows. 1,6-Ditrityl-D-mannitol was benzoylated and then detritylated the free hydroxyl groups of the resulting 2,3,4,5-tetrabenzoyl-D-mannitol were esterified with p-toluenesulfonyl chloride and the l,6-ditosyl-2,3,4,5-tetrabenzoyl-D-mannitol thus formed was treated with sodium iodide in acetone to form the diiododidesoxy tetrabenzoate. 

Lehn and Potvin (1988) have prepared an interesting chiral diamino ether based on the N,A -dimethyl-l,5-diamino-3-oxapentane structure. Starting with a ditosylate derivative of D-mannitol, they were able to produce the 2,5-anhydro-l,6-di-C-(jV-methyl)amino-l,6-dideoxy-3,4-di-0-methyl-D-mannitol as shown. 

O-Benzylidene fR-J, ditosyl 1,4-An-hydro-3,5-0- fR J -benzylidene-2,6-di-O-tosyl-D-mannitol... 

Ditrityl, 3,4-ditosyl 2,5-Anhydro-3,4-di-0-tosyl-l,6-di-0-trityl-D-mannitol [84446-95-7]... 

Ditosyl, 2,3,4,5-tetra-Ac 2,3,4,5-Tetra-0-acetyl-l,6-di-0-tosyl-D-mannitol C28H34O14S2 658.7... 

Ditosyl, 1,2,5,6-tetra-Ac 1,2,5,6-Tetra-0-acetyl-3,4-di-0-tosyl-D-mannitol [20706-75-6]... 

The two units (56) and (57) which are differentially-protected versions of a chiral array found in ionophoric antibiotics such as zincophorin, have been prepared from the D-mannitol-derived ditosylate (58) by means of regioselective openings of epoxides (Scheme 12).45... 

The [l8]-crown-6 compound (11) and its isomer with the syn-alignment of the two pyranoside moieties have been synthesized in 14 and 8 yield respectively from methyl 4,6- -benzylldene-a-D-glucopyranoside by alkylation with diethyleneglycol ditosylate a variety of derivatives with different solubility and complex form-Ing characteristics were prepared from compound (11). The bls-dianhydro-D-mannltolo-30-crown-10 derivative (12) was similarly prepared in 14 yield from 1,4 3,6-dianhydro-D-mannitol both compound (12) and its 1 1 1 complexes with primary ammonium cations... 

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