Terf-Butylacetylene

The head-to-head dimerization with formation of a butatriene derivative was very scarcely observed as the main catalytic route (Scheme 10.19, cycle B). Nevertheless, this was the case with benzylacetylene in the presence of RUH3CP (PCy3) as catalyst precursor in tetrahydrofuran at 80°C which gave more than 95% of (Z)-l,4-diben-zylbutatriene [66], and with terf-butylacetylene with two efficient catalytic systems capable ofgenerating zero-valent ruthenium species, RuH2(PPh3)3(CO) and Ru(cod) (cot) in the presence of an excess of triisopropylphosphine, which led to (Z)-l,4-di-tert-butylbutatriene as the major compound [71-73]. 

Hagele, G.. Goudetsidis. S., Wilke, E., Seega, J., Blum, H., and Murray, M., Synthesis and properties of compounds related to l-terf-butylacetylene-2-phosphonic acid and l-teri-butylethane-l,2,2-triph-osphonic acid. Sterically overcrowded phosphoms compounds. Part 1, Phosphorus, Sulfur Silicon Relat. Elem., 48, 131, 1990. 

Khojasteh et al. [473] reported that 2-phe-nyl-2(l-piperidinyl)propane is the most selective in vitro inhibitor for use in reaction phenotyping. New inhibitors have been considered based on structure-activity relationships [590]. The effect of a K262R substitution on inhibition by several drugs has been noted by Hollenbeig and his associates [591], and Thr-302 has been imphcated (by the same group) in irreversible inactivation by terf-butylacetylene [592]. 

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