Desilylative cross-dimerization

The rhodium-catalyzed desilylative cross-dimerization of terf-propargylal-cohols with bis(trimethylsilyl)acetylene was also developed (Scheme 4.104)... 

The products can undergo palladium-catalyzed desilylative arylation with aryl halides and, thus, various dihydrofuran derivatives can be prepared by the sequence of cross-dimerization/arylation/cyclization. 

The successive dimerization sequence was pursued as illustrated in Scheme 3.16. 50 was subjected to a Pd/Cu cross-coupling with monomer 16 to afford the polymer-supported dimer 51. Two-thirds of 51 was then treated with CH3I affording liberated dimer 25 in 71% yield over two steps. The remaining one-third of the polymer-supported dimer 51 underwent desilylation with tetra-... 

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