Insertion of 1-t-butylpropyne into singly tucked-in permethyltitanocene. Synthesis, crystal structure of product and transition-state geometry

0492089 - ÚFCH JH 2019 RIV NL eng J - Článek v odborném periodiku
Pinkas, Jiří - Mach, Karel - Kubišta, Jiří - Horáček, Michal - Szarka, K. - Gyepes, R.
Insertion of 1-t-butylpropyne into singly tucked-in permethyltitanocene. Synthesis, crystal structure of product and transition-state geometry.
Journal of Molecular Structure. Roč. 1167, SEP 2018 (2018), s. 180-186. ISSN 0022-2860. E-ISSN 1872-8014
Grant CEP: GA ČR(CZ) GA17-13778S
Institucionální podpora: RVO:61388955
Klíčová slova: internal alkynes * reduction * complexes * density * ethene * Titanocene
Obor OECD: Physical chemistry
Impakt faktor: 2.120, rok: 2018

The singly tucked-in titanocene [(eta(5)-C5Me5)Ti-III{eta(5):eta(1)-C5Me4(CH2)}] (1) reacted with one equivalent of 1-tert-butylpropyne to yield the propenyl-tethered regioisomer [(eta(5)-C5Me5)Ti(eta(5):eta(1)-C5Me4CH2C(t-Bu) = kappa CMe)] (3). The exclusive formation of paramagnetic 3 was proved experimentally and steric reasons were clarified by DFT calculation of transition state which involves both 7r-systems on the alkyne for bonding interaction with the metal and with sp(2) carbon atom of exomethylene group of I. The obtained compound 3 is by 40 kJ/mol lower in energy than its hypothetical isomer having t-Bu group on C-alpha of the tether. (C) 2018 Elsevier B.V. All rights reserved.
Trvalý link: http://hdl.handle.net/11104/0285654