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Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

Komprimiertes CO2 löst die Bildung amphiphiler supramolekularer Prolinassoziate in Wasser aus, die die asymmetrische Aldolreaktion ohne irgendwelche Additive katalysieren. Komprimiertes CO2 kann die Größe der Assoziate und anschließend die Katalysatoraktivität und ‐ selektivität dynamisch regulieren. Außerdem ermöglicht es eine einfache Trennung und Reinigung, was den Prozess nachhaltig und rezyklierbar macht. [ABSTRACT FROM AUTHOR]