Research - Dr. Justik’s Group
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Synthesis and Structure of Synthesis and Structure of Hypervalent Iodine CompoundsHypervalent Iodine Compounds
The concept The concept ““hypervalent iodinehypervalent iodine”” refers to the unique refers to the unique bonding interaction in iodine(III) and (V) compounds:bonding interaction in iodine(III) and (V) compounds:
Hypervalent Iodine Hypervalent Iodine CompoundsCompounds
Hypervalent iodine oxidants were the original Hypervalent iodine oxidants were the original ““greengreen”” reagents replacing many toxic metals (lead and reagents replacing many toxic metals (lead and thallium) in important synthetic transformations:thallium) in important synthetic transformations:
R1
R2
PhI(OH)OTs
O
R1
R2
n n95% MeOH, RT
+ +
I
+ TsOH
R1
R2
O
R1
R2
n n
+Tl(NO3)3 + TlNO3 + 2 HNO3MeOH, RT
Resaerch InterestsResaerch Interests
Synthesis and ReactivitySynthesis and Reactivity
Improvement of Improvement of ““greengreen”” synthetic methodology synthetic methodology using hypervalent iodineusing hypervalent iodine
Exploration of Exploration of hetereocyclic syntheseshetereocyclic syntheses
Preparation of novel Preparation of novel iodinanes of interest iodinanes of interest from an intellectual from an intellectual curiosity or synthetic curiosity or synthetic challenge aspectchallenge aspect
StructureStructure
In collaboration with Dr. In collaboration with Dr. John Protasiewicz at John Protasiewicz at Case Western Reserve Case Western Reserve University explore new University explore new iodinanes using X-ray iodinanes using X-ray crystallographycrystallography
Characterize novel Characterize novel iodinanes of interest iodinanes of interest from an intellectual from an intellectual curiosity or synthetic curiosity or synthetic challenge aspectchallenge aspect
Hydroxy(tosyloxy)iodobenzeneHydroxy(tosyloxy)iodobenzene““KoserKoser’’s Reagents Reagent””
HTIBHTIB
A mild and useful oxidant that A mild and useful oxidant that
mimics elemental brominemimics elemental bromine
MW 392.22 g/molMW 392.22 g/mol
11HH-1-hydroxy-5-methyl-1,2,3--1-hydroxy-5-methyl-1,2,3-benziodoxathiole 3,3-benziodoxathiole 3,3-DioxideDioxide
HMBIHMBI
A compact heterocyclic A compact heterocyclic equivalent of HTIBequivalent of HTIB
MW 314.10 g/molMW 314.10 g/mol
I OHO S
O
O
I
O
S
O
O
OH
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Improving Improving ““greengreen”” methods with HMBI - MWJ methods with HMBI - MWJ
R1
R2
PhI(OH)OTs
O
R1
R2
n n95% MeOH, RT
+ +
I
+ TsOH
R1
R2
O
R1
R2
n n95% MeOH, RT
+ +S
OHI
O OS
OI
O O
OH
recover, recycle, reuse
HMBI
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
O
OH
HMBI
MeOH, reflux 20 hrO
O
R'
R R R'
an Isoflavone
NH2
O
HMBI
CH3CN, refluxR R
NH3
reduced HMBI
NaOAc, Ac2OHN
OR
IO
SO
O
OH
O
+H2O
O
OH
-hydroxyketone
+I
OHSO
O
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Heterocyclic SynthesisHeterocyclic Synthesis
R C C I Ph
Nu:
C C I PhNu
R
C CNu
R
H+
C CI PhNu
R H
- PhI
1,2-rearrangement
C CR Nu
NuR
1,5-insertion
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Heterocyclic Synthesis Heterocyclic Synthesis (Melanie Knowlton (Melanie Knowlton ’’10, 10, Rachael Carmichael Rachael Carmichael ‘‘12)12)
C C I C C IO
C CO
O
O CCH
1,5-insertion-aryl C-H
O3S O3S
[Red I]
not observed
C
O
CH
1,5-insertion-alkyl C-H
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Attempted Heterocyclic Synthesis – Attempted Heterocyclic Synthesis – (Heather (Heather Sopher Sopher ‘‘09, Samantha Kristufek 09, Samantha Kristufek ’’11?)11?)
Ph I C C Ph
N O
N OPh
OTs
OTs
???
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Attempted Heterocyclic Synthesis – Attempted Heterocyclic Synthesis – (Heather (Heather Sopher Sopher ‘‘09, Samantha Kristufek 09, Samantha Kristufek ’’11)11)
Ph I C C Ph
N O
NO Ph
OTs
OTs
OTs
I
PhH
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Heterocyclic SynthesisHeterocyclic Synthesis
R C C I Ph
Nu:
C C I PhNu
R
C CNu
R
H+
C CI PhNu
R H
- PhI
1,2-rearrangement
C CR Nu
NuR
1,5-insertion
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Synthesis of a Novel Phenyliodonium Betaine - Synthesis of a Novel Phenyliodonium Betaine - MWJMWJ
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Synthesis of a Novel Phenyliodonium Betaine - Synthesis of a Novel Phenyliodonium Betaine - MWJMWJ
Brianne Sawders (‘12) is currently exploring the limits of the Suzuki reaction with this betaine
Synthesis with Hypervalent Synthesis with Hypervalent IodineIodine
Other long-term targets of interestOther long-term targets of interest
R
I
NaOCl
pH 8.2
R
IOO
TsOHI
OOTsR
I-R and I-S isomers observed
I
OTs
H H
Chirality at Iodine
Aromatic Iodine
base
I
OTs
H
I
" "
iodaanthracene
decomposes
colorless green
Structural StudiesStructural Studies
Structural Confirmation of an alkenyliodonium salt with Structural Confirmation of an alkenyliodonium salt with a pyridine a pyridine NN-oxide moiety-oxide moiety
Structural StudiesStructural Studies
Synthesis of a novel phenyliodinium betaineSynthesis of a novel phenyliodinium betaine
Structural StudiesStructural Studies
First example of a protonated iodosobenzene derivativeFirst example of a protonated iodosobenzene derivative
N
HN
I 1) AcOOH, AcOH, 40 oC
2) TsOH, CH3CN
N
NI
OHTsO
1919
AcknowledgementsAcknowledgements
My Students:Michelle Borkovec ‘06Alyssa Zimmerman ‘08.Heather Sopher ’09Michael Hughes ’09 Amanda Dechant ’09 Alex Ekstrom (biology) ’08 Melanie Knowlton ’09 Rocky Viggiano ‘09Samantha Kristufek ’11 Danielle Bittner ’11 Rachael Carmichael ’12 Brianne Sawders ’12Brandon Blanchard ‘12
Kathryn Sauka ‘14Alexis Rowley‘15Nick Burton‘15Anita Brkic ’15Johnny Lorigan’15 Zak Ekstrom ’15