501072-54-4

Upstream product

• 4526-07-2 1,4-bis(trimethylsilyl)-1,3-butadiyne 
• 1710-98-1 p-tert-butyl benzoyl chloride 
• 558-13-4 carbon tetrabromide 

Downstream Products

• 1416355-61-7 C₃₂H₂₆Br₄ 
• 501072-60-2 [6-(4-t-butylphenyl)-1,3,5-hexatriynyl]trimethylsilane 

Relevant academic research and scientific papers

Synthesis, characterization, and solid-state polymerization of cross-conjugated octatetraynes

Two series of cross-conjugated 1,3,5,7-octatetraynes (1a-1l and 6a-6d) have been synthesized. UV-vis spectroscopic analysis shows that pendent groups connected to the cross-conjugated skeleton have little effect on the λmax energies, irrespective of whether the groups are electron withdrawing or donating. A number of the isolated products readily give crystals suitable for X-ray crystallography, and the solid-state structural properties of five derivatives (1k, 1l, 6a, 6c, and 6d) have been examined by X-ray crystallographic analysis. Parallel packing of the polyynes in the solid state indicates that four of the five samples are potentially suitable for topochemical polymerization, based on solid-state packing parameters θ, R, and d. Attempts to effect a solid-state reaction have been explored through UV-vis and γ-ray irradiation as well as thermal heating. The course of these reactions was monitored by differential scanning calorimetry (DSC) analysis, as well as UV-vis and solid-state 13C NMR spectroscopy (for 1d, 1j, 1k, and 6d), which offered evidence of polymer formation from these reactions. Structural determination of the product(s), however, remains elusive.

Chiral propargyl alcohols via the enantioselective addition of terminal Di- and triynes to aldehydes

The enantioselective addition of di- and triynes to aldehydes is presented, including the first examples of an asymmetric triyne addition. Modification of the Carreira alkynylation protocol shows that addition of diynes and triynes to α-branched aldehydes can be complete in as little as 4 h, and these reactions give good yields and enantioselectivities (up to 98% ee) for di- and triynes tested (aryl, alkyl, and silyl). It is shown for two cases (20 and 24) that products of this asymmetric addition reaction can undergo further manipulation (desilylation and triazole formation) without affecting the enantiopurity.

Synthesis of unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes via alkylidene carbenoid rearrangements

Unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes are synthesized in four steps from commercially available aldehydes or carboxylic acids. The key step in this process involves a Fritsch-Buttenberg-Wiechell rearrangement, in which an alkylidene carbenoid intermediate subsequently rearranges to the desired polyyne. This rearrangement proceeds under mild conditions, and it is tolerant of a range of functionalities. In general, the procedurally facile formation of the dibromoolefinic precursors, in combination with the effectiveness of the rearrangement step, makes this procedure an attractive alternative to traditional methods for di- and triyne synthesis that utilize palladium or copper catalysis.