Synthesis of Diynes and Tetraynes from in Situ Desilylation/Dimerization of Acetylenes

Abstract

[reaction: see text]. An efficient method for the in situ desilylation/oxidative dimerization of (trialkylsilyl)acetylenes is described. This protocol avoids the complications encountered with sensitive diynes by eliminating the deprotection and isolation steps. Various aromatic and alkyl diynes and tetraynes can be synthesized in a straightforward manner in good yields (82-99%) from TIPS-protected acetylenes. This method facilitates the efficient synthesis of novel tetrayne-bridged acetylenic cyclophanes 6 and 7 in a direct manner.

Palladium‐Catalyzed Trimerizations of Terminal Arylalkynes: Synthesis of 1,3‐Diaryl‐2‐arylethynyl‐1,3‐butadienes[1]

“…Elemental analysis: Laboratory for elemental analyses at National Cheng Kung University. 1-Ethynyl-3,5-dimethoxybenzene (4c), [31] 1-ethynyl-3,5-dimethylbenzene (4e), [32] methyl 4-ethynylbenzoate (4i), [33] 9-ethynylanthracene (4p), [34] 1-phenyl-3-methylbut-3-en-1-yne (9a), [35] 2-phenyloct-1-en-3-yne (9b), [36] 1,3-diphenylbut-3-en-1-yne (9c), [14d] and 1,3-diA C H T U N G T R E N N U N G (4-anisyl)but-3-en-1-yne (9d) [14d] were prepared according to or similar to published procedures. Other compounds, which are not mentioned in the experimental section, are commercially available.…”

Macrocycles Based on Phenylacetylene Scaffolding

“…PTrM 327 was also constructed by similar synthetic methods. The Fallis group prepared the dimeric PTeM 332 and the strained tetrayne 333 (Scheme 8.72) [104]. Sonogashira cross-coupling of 334 with 1,4-diethynylbenzene gave hexayne 335.…”

“…The organic phase was washed thoroughly with HCl (1 m) until all pyridine had been removed, and the organic phase was dried and concentrated to yield a crude solid. Column chromatography (petroleum ether/CH 2 Cl 2 , 2:1) yielded 332 (16 mg, 5 %) as an orange solid and 333 (155 mg, 46 %) as a red solid [104].…”

Synthese und Strukturanalyse von eindimensionalen sp‐hybridisierten Kohlenstoffketten

“…[11] Eine andere Strategie ist die Bildung einer internen Dreifachbindung aus anderen funktionellen Gruppen. Ein typisches Beispiel ist die Fritsch-ButtenbergWiechell(FBW)-Umlagerung von Alkylidencarbenoiden (Schema 2 b).…”