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Staudinger reaction of azides derived from levoglucosan.
Mitrovský, Ondřej ; Trnka, Tomáš (advisor) ; Řezanka, Michal (referee)
This bachelor thesis is focused on research of reactivity of azido derivatives of levoglucosan with triphenylphosphine and tris(pyrrolidine)phosphine. The ultimate goal of this thesis was preparation of until now unpublished phosphazenes to make them available for practical utilization. Two of them were successfully prepared in crystallic form. Better results were with 2- or 4-azido derivatives of levoglucosan. In general reactivity of anhydro derivatives with azido group at C-3 were substantially lower, moreover the product mostly failed to crystallize.
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Synthesis of monosubstituted derivatives of cyclodextrins
Řezanka, Michal
1 Synthesis of monosubstituted derivatives of cyclodextrins Abstract This thesis is focused on a preparation of a set of exactly defined monosubstituted derivatives of -CD for subsequent utilization in organic synthesis. Cinnamyl or allyl group is very suitable for the preparation of monosubstituted derivatives of CD, because these groups contain nonaromatic double bond, which can be widely modified. Peracetylated 2I -O-, 3I -O-, and 6I -O-allyl and 2I -O- and 3I -O-cinnamyl derivatives of -CD mentioned in this thesis were prepared in yields 3.7 - 13 %. Position of allyl and cinnamyl group was determined by 2D NMR techniques. Possibility of derivatization of allyl and cinnamyl derivatives was exemplified by transformation of peracetylated 2I -O-, and 6I -O-allyl and 3I -O-cinanmyl derivatives to peracetylated 2I -O-, 3I -O-, and 6I -O-formylmethyl derivatives via reductive ozonolysis. These aldehydes were oxidized by Jones reagent to 2I -O-, 3I -O-, and 6I -O-carboxymethyl derivatives. Keywords: cyclodextrins, monosubstitution, allyl, cinnamyl, formylmethyl, carboxymethyl
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Synthesis and properties of monosubstituted derivatives of cyclodextrins
Řezanka, Michal ; Jindřich, Jindřich (advisor) ; Kraus, Tomáš (referee) ; Lhoták, Pavel (referee)
This Ph.D. thesis deals with synthesis of monosubstituted cyclodextrin derivatives and investigating their properties. Alkylation of -cyclodextrin with allyl or cinnamyl bromide followed by peracetylation of remaining hydroxyl groups and separation of isomers resulted in the set of peracetylated 2I - O-, 3I -O- and 6I -O-alkylated cyclodextrins in up to 27% yields. Oxidative cleaveage of peracetylated allyl or cinnamyl derivatives resulted in a complete set of peracetylated 2I -O-, 3I -O- and 6I -O- formylmethyl or carboxymethyl derivatives which are useful precursors for preparation of regioselectively monosubstituted derivatives of -cyclodextrin. Moreover, a quick method to recognize single 2I -O-, 3I -O- and 6I -O- monosubstituted peracetylated cyclodextrins from each other using only 1 H NMR spectrum has been proposed. Ru-carbene complex catalyzed cross-metathesis of monoallyl -, -, and -cyclodextrins with perfluoroalkylpropenes resulted in the formation of the corresponding perfluoroalkylated cyclodextrins. The reactions proceeded under standard reaction conditions and the desired compounds were obtained in reasonable yields. Dynamic light scattering measurements proved the ability of the prepared compounds to aggregate in water solution forming nanoparticles in the range of tens and...
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Staudinger reaction of azides derived from levoglucosan.
Mitrovský, Ondřej ; Trnka, Tomáš (advisor) ; Řezanka, Michal (referee)
This bachelor thesis is focused on research of reactivity of azido derivatives of levoglucosan with triphenylphosphine and tris(pyrrolidine)phosphine. The ultimate goal of this thesis was preparation of until now unpublished phosphazenes to make them available for practical utilization. Two of them were successfully prepared in crystallic form. Better results were with 2- or 4-azido derivatives of levoglucosan. In general reactivity of anhydro derivatives with azido group at C-3 were substantially lower, moreover the product mostly failed to crystallize.
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Synthesis of monosubstituted derivatives of cyclodextrins
Řezanka, Michal
1 Synthesis of monosubstituted derivatives of cyclodextrins Abstract This thesis is focused on a preparation of a set of exactly defined monosubstituted derivatives of -CD for subsequent utilization in organic synthesis. Cinnamyl or allyl group is very suitable for the preparation of monosubstituted derivatives of CD, because these groups contain nonaromatic double bond, which can be widely modified. Peracetylated 2I -O-, 3I -O-, and 6I -O-allyl and 2I -O- and 3I -O-cinnamyl derivatives of -CD mentioned in this thesis were prepared in yields 3.7 - 13 %. Position of allyl and cinnamyl group was determined by 2D NMR techniques. Possibility of derivatization of allyl and cinnamyl derivatives was exemplified by transformation of peracetylated 2I -O-, and 6I -O-allyl and 3I -O-cinanmyl derivatives to peracetylated 2I -O-, 3I -O-, and 6I -O-formylmethyl derivatives via reductive ozonolysis. These aldehydes were oxidized by Jones reagent to 2I -O-, 3I -O-, and 6I -O-carboxymethyl derivatives. Keywords: cyclodextrins, monosubstitution, allyl, cinnamyl, formylmethyl, carboxymethyl
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