We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
How to Bend a Cumulene.
- Authors
Barquera‐Lozada, José Enrique
- Abstract
Allenes (carbodicarbenes) and [3]cumulenes are linear carbon chains that can be bent when the terminal group has a strong carbene nature. This bending can be quite pronounced in allenes but not in [3]cumulenes. In this study, how N‐heterocyclic or cyclic (alkyl)(amino) carbene (NHC and CAAC, respectively) terminal groups can modify the linear structure of [n]cumulenes has been analyzed. A low π acidity of the terminal carbene affects the linearity of [2n]cumulenes. Indeed, it has been found that the NHC [4]cumulene is extremely bent, contrary to classical [4]cumulenes. The predicted NHC [4]cumulene or tricarbodicarbene has two lone pairs and the π electrons are delocalized over the whole molecule. More significantly, DFT calculations have shown that this bent [4]cumulene is very stable, considerably more so than the corresponding [3]cumulene, which has been elusive to synthesize. Remarkably, calculations have shown that all the NHC [2n]cumulenes are more than 25 kcal mol−1 more stable than the [2n−1]cumulenes.
- Subjects
CUMULENES; NONBONDING electron pairs; ALLENE
- Publication
Chemistry - A European Journal, 2020, Vol 26, Issue 20, p4633
- ISSN
0947-6539
- Publication type
Article
- DOI
10.1002/chem.202000025