How is (1R,3E,7E,11R)-1,5,5,8-Tetramethyl-12-oxabicyclo[9.1.0]dodeca-3,7-diene (CAS: 19888-34-7) typically synthesized?

(1R,3E,7E,11R)-1,5,5,8-Tetramethyl-12-oxabicyclo[9.1.0]dodeca-3,7-diene can be synthesized via a stereoselective ring expansion of a cyclic alkyne. Common methods include using palladium catalysts in the presence of tributyltin hydride and sodium bis(trimethylsilyl)amide (NTMS2). The reaction typically yields a high enantiomeric excess, making it suitable for chiral applications. Other methods involve Wittig olefination followed by ring closure, which allows for good control over the stereochemistry and yields.