Cross-linking of starch with bifunctional precursors of nitroalkenes.
Granular starch was cross-linked with 1,3-di-O-acetyl-2-nitro-1,3-propanediol (1), 1,3-di-O-pivaloyl-2-nitro-1,3-propanediol (2), 2-nitro-3-O-pivaloyl-1-propene-3-ol (3), 1,3-di-O-acetyl-aci-2-nitro-1, 3-propanediol (4), 1,3-di-O-pivaloyl-aci-2-nitro-1,3-propanediol (5) and 1,6-di-O-acetyl-2,5-dinitro-1,6-hexanediol (6). The bifunctional precursors for the nitro-alkenes 1, 2, 3, and 4 were readily synthesized in high yields from nitromethane, paraformaldehyde and acetic anhydride (1, 3) or pivaloyl chloride (2, 4), respectively. The reaction rate for the cross-linking was very high, and for 1 and 3, the reaction reached completion within 1 h (at room temperature). The swelling capacities of the products obtained when starch was cross-linked with precursors for the nitroalkenes 1-4 and 6 were lower in comparison to epichlorohydrin cross-linked starch. These results indicate a high reaction efficiency at low degrees of substitution. Cross-linked 2-nitroalkyl starch ethers were synthesized in a one-pot synthesis by addition of 1 or 3 and 2-nitroalkyl acetates to granular suspensions of starch.
Heeres
A
A
TNO Nutrition and Food Research Institute, Groningen, The Netherlands.
van Doren
H A
HA
Gotlieb
K F
KF
Bleeker
I P
IP
Kellogg
R M
RM
D000478:Alkylation; D002240:Carbohydrate Sequence; D003432:Cross-Linking Reagents; D008969:Molecular Sequence Data; D009574:Nitro Compounds / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D014783:Viscosity
D003432:Cross-Linking Reagents; D009574:Nitro Compounds; D013213:Starch