Test 4

Question 1

First OM complex ?. Year of synthesis?

Answer 1

ziese’s salt. 1827

Question 2

ziese’s salt structure

Answer 2

contains ethylene

Question 3

Carbonyl bond as ligand in OM complex

Answer 3

long due to sigma donation from carbonyl carbon and pi backdonation into antibonding orbital of carbonyl. CO is a weak lewis base. Can bind to zero-valent metal.

Question 4

Most common type binding of CO

Answer 4

terminal

Question 5

prefix that indicates Coordination sites occupied

Answer 5

u

Question 6

prefix that indicates number of atoms through which ligand binds to metal

Answer 6

m

Question 7

Why is grignard reactive

Answer 7

C (soft base) bound to Mg (hard acid). not stable

Question 8

classical ligands

Answer 8

don’t bind with zero-valent metals. Good lewis bases.

Question 9

Ligands similar to CO

Answer 9

CS, CSe, CN-, N2, NO+ (linear), NO- (bent)

Question 10

fischer carbenes

Answer 10

contain one or two e-neg heteroatoms bound to carbene carbon

Question 11

carbene

Answer 11

contains metal-carbon double bond

Question 12

schrock carbenes

Answer 12

contain just H or C bonded to carbene carbon

Question 13

? carbenes are more stable due to enhanced pi backdonation

Answer 13

fischer

Question 14

two main classes of OM reactions

Answer 14

change OX state, and don’t change ox state

Question 15

2 basic types of OM rxns that don’t change OX state

Answer 15

association, dissociation

Question 16

association increases/decreases CN?

Answer 16

increases

Question 17

dissociation increases/decreases CN?

Answer 17

decreases

Question 18

oxidative addition effect on CN? on ox state?

Answer 18

increase, increase

Question 19

reductive elimination effect on CN? on ox state?

Answer 19

decrease, decrease

Question 20

cyclometallation

Answer 20

incorporates metal into an organic ring

Question 21

most common type of cylcometallation

Answer 21

orthometallation

Question 22

orthometallation

Answer 22

Ortho C-H from an adjacent phenyl group forms the ring

Question 23

1,1 insertion

Answer 23

bonds to inserted molecule are on same atom

Question 24

1,2 insertion

Answer 24

bonds to inserted molecule are on adjacent atoms

Question 25

3 possible mechs of CO insertion

Answer 25

direct, CO migration, alkyl migration

Question 26

1st tom flood experiment

Answer 26

CH3Mn(CO)5 w/ *CO. *CO added cis to methyl. Ruled out direct CO insertion.

Question 27

2nd tom flood experiment

Answer 27

Mn(CO)5*COCH3 heated. CO dissociated. *CO appeared cis to methyl. Proved carbonyl or alkyl migration but not which one.

Question 28

3rd Tom flood experiment

Answer 28

Mn(CO)5COCH3 with radioactive carbonyl in cis position heated. Proved alkyl migration. Cis and trans labelled products.

Question 29

hydride elimination

Answer 29

transfer of H from ligand to metal

Question 30

most common hydride elimination

Answer 30

beta-H elimination

Question 31

reverse of B-H elimination

Answer 31

1,2 insertion

Question 32

alkyl compounds with beta hydrogens are more/less stable

Answer 32

less

Question 33

Abstraction

Answer 33

elimination rxn in which CN of metal does not change. Usually external lewis acid removes substituent from ligand.

Question 34

active catalyst

Answer 34

is in the cycle itself