Lecture_9_18Electron

Lecture_9_18Electron - Chem 310 Lecture Module 9 The...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Chem 310 Lecture Module 9 The 18-Electron Rule and Organometallics
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Organometallic Chemistry Organometallic compound: “one that possesses a metal-carbon bond” cludes transition metal carbonyls phosphines organoboron organosilicon Includes transition metal carbonyls, phosphines, organoboron, organosilicon chemistry, but not cyano complexes. Best defined as chemistry of very low-valent metal complexes (ie, close to zero). ome compounds form useful catalysts for a few industrial reactions, tho’ limited in scope The 18-electron rule riginally based on concept from Lewis gands are L. bases, metals are L. acids. Some compounds form useful catalysts for a few industrial reactions, tho limited in scope Originally based on concept from Lewis ligands are L. bases, metals are L. acids. Stability related to attaining noble gas configuration for metal. The sum of electrons on the metal plus electrons donated to the metal was called the EAN. •When EAN = 36 (Kr); 54 (Xe) or 86 (Rn) the EAN rule is said to be obeyed. •More easily stated: when the metal achieves an outershell configuration of ns 2 (n-1)d 10 np 6 , there will be 18 electrons in the valence orbitals and a closed, stable configuration. I.e., it more simply refers to the total capacity of 9 orbitals (one set each of s, p and d) •Rule of thumb is obeyed with high frequency for organometallic compounds, especially ose with carbonyl and nitrosyl (NO) ligands: Especially electron ch metals (ie one in those with carbonyl and nitrosyl (NO) ligands: Especially electron-rich metals (ie., one in low oxidation state), good π –acceptor ligands favor rule
Background image of page 2
Reason for 18-Electron Rule – rooted in MO theory For an octahedral complex, the most stable arrangement will be that in which all of
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/28/2011 for the course CHEM 310 taught by Professor Nazar during the Fall '09 term at Waterloo.

Page1 / 13

Lecture_9_18Electron - Chem 310 Lecture Module 9 The...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online