The conjugation stabilization of 1,3-butadiyne is zero

Donald W Rogers; Nikita Matsunaga; Andreas A Zavitsas; Frank J McLafferty; Joel F Liebman

doi:10.1021/ol030019h

The conjugation stabilization of 1,3-butadiyne is zero

Org Lett. 2003 Jul 10;5(14):2373-5. doi: 10.1021/ol030019h.

Authors

Donald W Rogers¹, Nikita Matsunaga, Andreas A Zavitsas, Frank J McLafferty, Joel F Liebman

Affiliation

¹ Department of Chemistry and Biochemistry, Long Island University, Brooklyn, New York 11201, USA. drogers@liu.edu

PMID: 12841733
DOI: 10.1021/ol030019h

Abstract

[reaction: see text] In contrast to 1,3-butadiene, the textbook example of "conjugation stabilization", G3(MP2) calculations yielding the enthalpy of hydrogenation Delta(hyd)H(298) of 1,3-butadiyne indicate that it is not stabilized by the conjugated configuration of its triple bonds. Differences between ethylenic and acetylenic pi bonds are examined in the light of CAS-MCSCF calculations on 1,3-butadiene and 1,3-butadiyne.