Polyols from Natural Oils using the Alkyne Zipper Reaction

Title: POLYURETHANE MATERIALS FORMED FROM UNSATURATED PLANT OILS VIA AN ALKYNE ZIPPER REACTION

Number/Link: US2017/0166679 US2017/0166680

Applicant/Assignee: IBM

Publication Date: 15-june-2017

“Gist”: Oils are turned into alkyne alcohols, ‘zippered’ and oxidized to polyols

Why it is interesting: This is yet  another IBM patent application about interesting, albeit somewhat exotic, chemistry and featuring only “prophetic” examples. In this case unsaturated natural oils are first converted into unsaturated alcohols and then into alkynes by bromination and elimination.  The internal alkynes are then converted to terminal alkynes by an “alkyne zipper reaction” and then into hydroxyl groups by hydroboration and epoxidation/ring-opening. This series of reactions should result in polyols having two primary- and one or more secondary OH groups, useful, for example, for the preparation of sound absorbing foams.

Reaction sequence according to the invention

Isocyanate-Free Polyurethanes Using Azide-Alkyne Click Chemistry

Title: SYNTHESIS OF POLYURETHANE POLYMERS VIA COPPER AZIDE-ALKYNE CLICK CHEMISTRY FOR COATINGS, ADHESIVES, SEALANTS AND ELASTOMER APPLICATIONS

 Number/Link: WO2014/122153

Applicant/Assignee: Sika

Publication date: 14-08-2014

Gist”: Polyurethane prepolymers capped with azides and alkynes are reacted using copper catalysis.

Why it is interesting: Because of safety, health and envriromental issues, isocyanate-free systems have clearly been gaining in importance the last few years.  Especially for coatings, adhesives and OCF applications, alternative curings systems are being developed. In the current invention an isocyanate-free system is based on the reaction between a prepolymer having at least two azide groups and a prepolymer having at least two alkyne groups. The reaction is copper catalyzed such that it can be performed at ambient temperature. The first prepolymer is (pref.)  prepared by reacting an isocyanate ended prepolymer with glycidol (2,3-epoxy-1-propanol) and subsequently with sodium azide. The second prepolymer is similarly prepared by reacting an isocyanate ended prepolymer with propargyl alcohol (2-propyn-1-ol).  The systems are said to be especially useful for roof coatings.

Example of an azide-alkyne reaction resulting in 1,4-disubstituded triazoles.

Example of an azide-alkyne reaction resulting in 1,4-disubstituded triazoles.