Copolymeric cyclodextrin polysiloxane stationary phases prepared from 6 A ,6 C ‐ and 6 A ,6 D ‐dialkenyl‐substituted β‐cyclodextrin

The syntheses of four new β‐cyclodextrin‐hexasiloxane copolymers from heptakis(2,3‐di‐ O ‐methyl)‐β‐cyclodextrin (2) by multi‐step processes are described. 6 A ,6 C ‐Di‐ O ‐[ p,p' ‐methylenebis(benzenesulfonyl)]hetakis(2,3‐di‐ O ‐methyl)β‐cyclodextrin (3) , which was prepared by the reaction of 2 with p,p' ‐methylenebis‐(benzenesulfonyl chloride), is a key intermediate for the preparation of permethylated 6 A ,6 C ‐bisalkenyl‐β‐cyclodextrins 5, 6 , and 9. Permethylated 6 A ,6 C ‐bissulfonate ester 4 , which was obtained from 3 by a methylation reaction under mild conditions, was reacted with sodium allyloxide or sodium ω‐undecenyloxide to produce permethylated 6 A ,6 C ‐bisallyl‐ (or bis‐ω‐undecenyl)‐β‐cyclodextrin 5 or 6 or was hydrolyzed with 2% sodium amalgam in methanol to yield diol 7. Compound 7 was oxidized with periodinane, followed by Wittig's reaction with methyltriphenylphosphonium iodide to give permethylated 6 A ,6 C ‐dideoxy‐6 A ,6 C ‐dimethylene‐β‐cyclodextrin (9). Treatment of 2 with p,p' ‐methylenebis(benzenesulfonyl chloride) or p,p' ‐biphenyldisulfonyl chloride gave bissulfonate esters 10 or 11 , respectively. Both of them were treated with sodium p ‐allyloxy‐phenoxide in DMF, followed by methylation, to form permethylated 6 A ,6 D ‐di‐ O ‐( p ‐allyloxyphenyl)‐β‐cyclo‐dextrin (16). Bisalkenes 5, 6, 9 and 16 were copolymerized with α,ω‐dioctyldecamethylhexasiloxane by a hydrosilylation process to give the cyclodextrin‐containing copolymers 17–20.