55956-33-7Relevant academic research and scientific papers
Et2SiH2 assisted the selective dimerization of terminal alkynes catalyzed by Cp*2UMe2
Wang, Ji Quan,Eisen, Moris S.
, p. 97 - 107 (2007/10/03)
A practical approach has been developed for the catalytic synthesis of short oligomers, dimers and/or trimers of terminal alkynes. The method allows control of the extent and, in some cases, the regiospecificity in the catalyzed oligomerization of terminal alkynes promoted by bis(pentamethylcyclopentadienyl)uranium dimethyl complex (Cp*2U(CH3)2, Cp= C5Me5). The metallocene precursor is known to promote the simultaneous production of a large number of differently sized oligomers in the presence of terminal alkynes. However, the addition of a specific secondary silane ensures the selective synthesis of short oligomers.
Controlling the catalytic oligomerization of terminal alkynes promoted by organoactinides: A strategy to short oligomers
Haskel, Ariel,Wang, Ji Quan,Straub, Thomas,Neyroud, Tal Gueta,Eisen, Moris S.
, p. 3025 - 3034 (2007/10/03)
A novel strategy has been developed for the catalytic synthesis of short oligomers, dimers and/or trimers, of terminal alkynes. The method allows control of the extent of and, in some cases, the regiospecificity in the catalyzed oligomerization of terminal alkynes promoted by bis(pentamethylcyclopentadienyl)actinide dimethyl complexes (Cp*2AnMe2; Cp* = C5Me5, An = Th, U). These metallocene precursors are known to promote the simultaneous production of a large number of differently sized oligomers in the presence of terminal alkynes. However, the addition of specific amines ensures the selective synthesis of short oligomers. Catalytic 'tailoring' to dimers or a mixture of dimers and trimers can be achieved by using nonbulky or bulky amines, respectively. The kinetics in the catalytic oligomerization of 1-hexyne, in the presence of i-BuNH2, mediated by Cp*2ThMe2 are first order in [alkyne], first order in [Th], and inverse first order in [amine]. Kinetic, spectroscopic, and mechanistic data argue that the turnover-limiting step involves the formation of the mono(amido)thorium acetylide complex with rapid insertion of the alkyne and protonolysis by the amine.
