Polyether tetraols

Tetrafunctional starters (such as pentaerythritol and ethylene diamine) are used to a small extent for the synthesis of high MW poly ethers. An interesting tetrafunctional starter is ethylene diamine. In the first step the alkylene oxide reacts with the -N-H groups forming a tetraol. By the polymerisation reaction of alkylene oxides initiated by the tetraol formed in situ, a high MW polyether tetraol is obtained ... 

Figure 4.39 The structure of polyether tetraols, block copolymers PO-EO, based on...

Novel macrobicyclic compounds have been prepared (151) from the tetraol obtained on de-O-benzylidenation of the bisgalactosido-18-crown-6 derivative aa-DD-117 in Figure 18. Selective tritylation of the two hydroxymethyl groups of the tetraol, followed by a base-promoted reaction with pentaethylene glycol ditosylate afforded aa-DD-155 with a polyether chain bridging the 4 and 4 positions of the D-galactopyranosidic rings across presumably the /3 face of the molecule. 

Tetraol or higher functionality polyether polyols are used to a lesser extent in flexible foams, especially when a high compression strength is required (for example in carpet underlay). 

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