Benzylic C(sp3)-H bond sulfonylation of 4-methylphenols with the insertion of sulfur dioxide under photocatalysis

Article abstract of DOI:10.1039/c8cc06567e

Sulfonylation of the benzylic C-H bond is developed through a three-component reaction of aryldiazonium tetrafluoroborates, 4-methylphenols and sodium metabisulfite (Na₂S₂O₅). The inorganic sulfite of sodium metabisulfite is used as the SO₂ surrogate. In this transformation, benzylic C(sp³)-H bond sulfonylation is achieved in the presence of a photocatalyst under visible light. A radical pathway involving the arylsulfonyl radical and intermolecular hydrogen atom abstraction is proposed.

Full text of DOI:10.1039/c8cc06567e

View Article Online
View Journal
ChemComm
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: X. Gong, J. Chen,
L. Lai, J. Cheng, J. Sun and J. Wu, Chem. Commun., 2018, DOI: 10.1039/C8CC06567E.
Volume 52 Number
1
4
January 2016 Pages 1–216
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
ChemComm
Chemical Communications
www.rsc.org/chemcomm
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1359-7345
COMMUNICATION
Marilyn M. Olmstead, Alan L. Balch, Josep M. Poblet, Luis Echegoyenet al.
Reactivity differences of Sc
first methanofullerene derivatives of Sc
3
N@C2n (2n
=
68 and 80). Synthesis of the
3
N@D5h-C80
rsc.li/chemcomm

Page 1 of 4
ChemComm
View Article Online
DOI: 10.1039/C8CC06567E

ChemComm
Page 2 of 4
View Article Online
DOI: 10.1039/C8CC06567E
!
.+2!422&
'HAOA8FFTY&O@<&M<8:OAJH&R8N&:8MMA<;&JPO&AH&oYpb;A:@FJMJ<O@8H<& g'Me;$!$
#4:73'1ꢀ$'2+&
&
'3`'''&
&
q
q
KKTf
KKTf
p
p
e;O99KTf.$
e9KTf&.$
t
h& e#o`p
h&e#o`p
& |& {o\tw& 3& QN& 1!#f& JM&
&|&{o\tw&3&QN&1!#f&R8N&PN<;&
&
'3`'''
e"!#f&8O&MJJG&O<GK<M8OPM<\&ꢀJR<Q<MY&JHFT&8&OM8:<&8GJPHO&J=& g'Me;$!$
t
O@<& ;<NAM<;& KMJ;P:O& I'& R8N& J9N<MQ<;& e1:@<G<& of\& 4<& AHNO<8;& J=& 'MeKKTfq& AH& O@<& M<8:OAJH& J=& rbG<O@TFbpYtb;AbC6ACb
:
JH:<AQ<;& O@8O& O@<& :JG9AH8OAJH& J=& 8MTF;A8UJHAPG& 9POTFK@<HJF& G(Y! @bOJFTF;A8UJHAPG& O<OM8=FPJMJ9JM8O<& H'& 8H;&
'
3`'''&
O<OM8=FPJMJ9JM8O<&8H;&KJO8NNAPG&G<O89ANPF=AO<&:JPF;&HJO&8NNANO& KJO8NNAPG&G<O89ANPF=AO<&e#o`p
|&{n\uu&3&QN&1!#f&PH;<M&O@<&
O@<&=JMG8OAJH&J=&K@<HJST&M8;A:8F\&2@<M<=JM<Y&8&K@JOJM<;JS& NO8H;8M;&:JH;AOAJHN\&ꢀJR<Q<MY&O@<&TA<F;&R8N&HJO&<H@8H:<;\&
8O8FTNAN&PH;<M&QANA9F<&FA?@O&AMM8;A8OAJH&R8N&AHOMJ;P:<;&AH&O@<& 2@<M<=JM<Y&AO&N<<G<;&O@8O&:JGKJPH;&G'&RJPF;&KJNNA9FT&8:O&8N&
M<8:OAJH&NTNO<GY&RAO@&8H&<SK<:O8OAJH&OJ&KMJQA;<&O@<&K@<HJST& 8H&AHO<MGJF<:PF8M&@T;MJ?<H&89NOM8:OAJH&M<8?<HO\&
M8;A:8F\& V=O<M& JKOAGAU8OAJH& J=& O@<& :JH;AOAJHNY& O@<& ;<NAM<;&
KMJ;P:O&I'ꢀR8N&?<H<M8O<;&AH&usz&TA<F;&R@<H&O@<&M<8:OAJH&R8N& &'(1+ꢀG?&1:JK<&AHQ<NOA?8OAJH&=JM&O@<&M<8:OAJH&J=&rbG<O@TFK@<HJFN&
:
&
G
Y&
2
!
K<M=JMG<;&AH&O@<&KM<N<H:<&J=&'MeKKTf
q
&PH;<M&qt&4&:JGK8:O& NJ;APG&G<O89ANPF=AO<Y&8H;&8MTF;A8UJHAPG&O<OM8=FPJMJ9JM8O<N&H&
=
FPJM<N:<HO& F8GK& 8O& MJJG& O<GK<M8OPM<Y& PNAH?& NJ;APG&
&
R1
HO
R1
DCE, 36 W CFL HO
G<O89ANPF=AO<&8N&O@<&NJPM:<&J=&NPF=PM&;AJSA;<&8H;&,8ꢀ!-
O@<&98N<&e$JM&;<O8AFNY&KF<8N<&N<<&#1'f\&
q
&8N&
Na S O
Ar
H
2
2
5
Ir(ppy) , NaHCO3
S
3
+
O
O
Ar N2BF4
p-Tol
H
S
R2
1
R2
“
SO2”
photocatalyst
3
2
+
O
O
HO
p-Tol N2BF4 solvent, 36 W CFL HO
3a: Ar = 4-MeC6H4, 75% yield
1a
2a
3a
3b: Ar = C H , 74% yield
&
6 5
3
c: Ar = 4-MeOC6H4, 68% yield
Ar
t
3d: Ar = 4- BuC6H4, 67% yield
S
%
).+2+ꢀG!&'HAOA8F&NOP;A<N&=JM&O@<&M<8:OAJH&J=&pYrYtbOMAG<O@TFK@<HJF&G'Y&
6 4
3e: Ar = 4-FC H , 70% yield
O
O
HO
3f: Ar = 4-ClC6H4, 50% yield
g: Ar = 4-BrC6H4, 48% yield
3h: Ar = 4-CF C H , 45% yield
NPF=PM&;AJSA;<Y&8H;&@bOJFTF;A8UJHAPG&O<OM8=FPJMJ9JM8O<&H'\&
&
3
3
6 4
3i: Ar = 3-MeC6H4, 51% yield
3j: Ar = 3-MeOC6H4, 42% yield
3k: Ar = 3-ClC6H4, 45% yield
4
AO@&O@<&JKOAGAU<;&:JH;AOAJHN&AH&@8H;Y&R<&O@<H&<SKFJM<;&
O@<& ?<H<M8FAOT& J=& O@AN& O@M<<b:JGKJH<HO& M<8:OAJH& J=&
MTF;A8UJHAPG& O<OM8=FPJMJ9JM8O<NY& rbG<O@TFK@<HJFN& 8H;&
NJ;APG&G<O89ANPF=AO<\&2@<&M<NPFO&AN&;ANKF8T<;&AH&289F<&o\&$AMNOFTY&
&M8H?<&J=&8MTF;A8UJHAPG&O<OM8=FPJMJ9JM8O<N&R<M<&<S8GAH<;&AH&
8
R
p-Tol
S
tBu
HO
Ph
H
p-Tol
O
O
S
S
HO
O
O
O
O
8
HO
t
H
O@<& M<8:OAJH& J=& NJ;APG& G<O89ANPF=AO<& RAO@& pYrYtb
OMAG<O@TFK@<HJF&G'\&'O&R8N&=JPH;&O@8O&8FF&M<8:OAJHN&KMJ:<<;<;&
NGJJO@FTY&8==JM;AH?&O@<&:JMM<NKJH;AH?&KMJ;P:ON&AH&GJ;<M8O<&
OJ&?JJ;&TA<F;N\&$PMO@<MGJM<Y&AO&N@JR<;&O@8O&O@<&?MJPKN&8O&O@<&
3l: R = Bu, 70% yield
3
3
m: R = 4-MeC6H4, 42% yield
n: R = 4-ClC6H4, 45% yield
3o, 53% yield
3p, n.d.
tBu
tBu
tBu
HO
p-Tol
p-Tol
p-Tol
S
S
S
O
O
O
O
O
O
?
AC9?bKJNAOAJH& J=& K@<HJF& R<M<& :MP:A8F& =JM& O@<& NP::<NN=PF& HO
HO
tBu
q, 25% yield
Et
3r, trace
OM8HN=JMG8OAJH\&$JM&AHNO8H:<Y&:JGKJPH;&I1&R8N&KMJ;P:<;&AH&
unz&TA<F;Y&R@AF<&HJ&;<NAM<;&KMJ;P:O&I5&R8N&J9O8AH<;&R@<H&rb
G<O@TFK@<HJF& R8N& <GKFJT<;& AH& O@<& M<8:OAJH& J=& @b
OJFTF;A8UJHAPG&O<OM8=FPJMJ9JM8O<&H'&RAO@&NJ;APG&G<O89ANPF=AO<\&
V;;AOAJH8FFTY&O@<&:JMM<NKJH;AH?&KMJ;P:O&I6ꢀ:JPF;&9<&8==JM;<;&
AH&psz&TA<F;&R@<H&rbG<O@TFbpYtb;AbC6ACb9POTFK@<HJF&G(&R8N& HO
PN<;& 8N& O@<& NP9NOM8O<\& ꢀJR<Q<MY& JHFT& 8& OM8:<& 8GJPHO& J=&
KMJ;P:O&I7ꢀJMꢀI8ꢀR8N&;<O<:O<;&R@<H&JH<&C6ACb9POTF&?MJPK&JH&
O@<&8MJG8OA:&MAH?&R8N&M<KF8:<;&9T&<O@TF&?MJPK&JM&:T:FJKMJKTF&
3
3s, trace
&
2
&
'NJF8O<;&TA<F;&98N<;&JH&NJ;APG&G<O89ANPF=AO<\&
p-Tol
H
Na S O
S
2
2
5
standard conditions
+
O
O
(1)
(2)
p-Tol N BF TEMPO (3.0 equiv) HO
2
4
1a
2a
3a, n.d.
p-Tol
Na2S2O5
S
O
O
standard
p-Tol N2BF4 2a conditions
H
HO
?
MJPK\&&
+
J& PH;<MNO8H;& O@<& M<8:OAJH& G<:@8HANGY& N<Q<M8F& :JHOMJF& HO
Ph
3
a, < 5%
2
<
SK<MAG<HON&R<M<&:8MMA<;&JPO\& 8N<;&JH&JPM&@TKJO@<NANY&O@AN&
1a
Ph
Ph
Ts
Ph
M<8:OAJH&RJPF;&PH;<M?J&8&M8;A:8F&K8O@R8T\&VN&<SK<:O<;Y&HJ&
M<8:OAJH&J::PMM<;&R@<H&2#+.-&R8N&8;;<;&e1:@<G<&pY&<L&of\&
V;;AOAJH8FFTY&O@<&8MTFNPF=JHTF&M8;A:8F&:JPF;&9<&OM8KK<;&9T&oYob
46%
p-Tol
H
H
S
O
O
HO
HO
;
AK@<HTF<O@<H<Y&F<8;AH?&OJ&O@<&:JMM<NKJH;AH?&KMJ;P:O&AH&rtz&
1
a
Na2S2O5
standard conditions
3a, < 5%
TA<F;&e1:@<G<&pY&<L&pf\&'HO<M<NOAH?FTY&:JGKJPH;&I6ꢀ:JPF;&9<&
tBu
+
+
(3)
tBu
HO
p-Tol N2BF4
p-Tol
8
8
@
==JM;<;& AH& uuz& TA<F;& R@<H& pYrYtbOMAG<O@TFK@<HJF& G'& R8N&
;;<;&AH&O@<&M<8:OAJH&J=&rbG<O@TFbpYtb;AbC6ACb9POTFK@<HJF&G(Y!
S
HO
2a
O
O
tBu 1b
tBu 3q, 77%
bOJFTF;A8UJHAPG& O<OM8=FPJMJ9JM8O<& H'
&
8H;& KJO8NNAPG&
&
G<O89ANPF=AO<&e1:@<G<&pY&<L&qf\&*<NN&O@8H&sz&J=&:JGKJPH;&I'ꢀ
R8N&;<O<:O<;&AH&O@<&M<8:OAJH&NTNO<G\&2@AN&M<NPFO&N@JR<;&O@8O& %).+2+ꢀH?&!JHOMJF&<SK<MAG<HON&e=JM&;<O8AFNY&KF<8N<&N<<&O@<&#1'f\
&
8
8
H&AHO<MGJF<:PF8M&@T;MJ?<Hb89NOM8:OAJH&KMJ:<NN&GA?@O&J::PMY&
+JM<& <S8GKF<N& =JM& O@<& M<8:OAJH& J=& rbG<O@TFbpYtb;AbC6ACb
H;&O@<&8;;AOAJH&J=&NP9NOM8O<&G'&:JPF;&?M<8OFT&KMJGJO<&O@<& 9POTFK@<HJF& G(Y! 8MTF;A8UJHAPG& O<OM8=FPJMJ9JM8O<N&
H& 8H;&
OM8HN=JMG8OAJH& J=& G(& OJ& AON& 9<HUTFA:& M8;A:8F\& +JM<JQ<MY& KJO8NNAPG&G<O89ANPF=AO<&AH&O@<&KM<N<H:<&J=&NP9NOM8O<&G'&R<M<&
H&a&'L!+2=6\Y&pnopY&FFY&obq&
2@AN&DJPMH8F&AN&k&2@<&0JT8F&1J:A<OT&J=&!@<GANOMT&pnSS&

Page 3 of 4
ChemComm
View Article Online
DOI: 10.1039/C8CC06567E
#
4:73'1ꢀ$'2+ꢀ
!.+2!422ꢀ
KM<N<HO<;&AH&1:@<G<&q\&2@<&TA<F;&J=&KMJ;P:O&I6&R8N&M<;P:<;&
R@<H&O@<&8GJPHO&J=&:JGKJPH;&G'&;<:M<8N<;&AH&O@<&M<8:OAJH\& 9<HUTFA:&!bꢀ&9JH;&O@MJP?@&8&O@M<<b:JGKJH<HO&M<8:OAJH&J=&
@AN&M<NPFO&KMJQA;<;&8;;AOAJH8F&<QA;<H:<&O@8O&:JGKJPH;&G' 8MTF;A8UJHAPG& O<OM8=FPJMJ9JM8O<NY& rbG<O@TFK@<HJFN& 8H;&
N<MQ<;&8N&8H&AHO<MGJF<:PF8M&@T;MJ?<H&89NOM8:OAJH&M<8?<HO&AH& NJ;APG& G<O89ANPF=AO<& PH;<M& K@JOJ:8O8FTNAN\& 2@<& AHJM?8HA:&
O@<&M<8:OAJH&KMJ:<NN\&'O&R8N&8NNPG<;&O@8O&O@<&M<G8ME89F<& NPF=AO<&J=&NJ;APG&G<O89ANPF=AO<&AN&PN<;&8N&O@<&1- &NPMMJ?8O<\&'H&
N<F<:OAQAOT&9<OR<<H&NP9NOM8O<N&G'&8H;&G(&GA?@O&8MAN<&=MJG& O@AN&OM8HN=JMG8OAJHY&9<HUTFA:&!eNK fcꢀ&9JH;&NPF=JHTF8OAJH&AN&
A?@<M&M<F8OAQ<&NO89AFAOT&J=&O@<&K@<HJST&M8;A:8F&;<MAQ<;&=MJG& M<8FAU<;&PH;<M&GAF;&:JH;AOAJHN&PH;<M&QANA9F<&FA?@O&AMM8;A8OAJH\&V&
JGKJPH;&G(&9T&NO<MA:&N@A<F;AH?&8H;`JM&O@<&AH:M<8N<;&<F<:OMJH& M8;A:8F& K8O@R8T& AHQJFQAH?& 8MTFNPF=JHTF& M8;A:8F& 8H;&
MA:@H<NN& J=& G(\& 2J& <SK8H;& O@<& NP9NOM8O<& N:JK<Y& M<8:OAJHN& AHO<MGJF<:PF8M&@T;MJ?<H&8OJG&89NOM8:OAJH&AN&KMJKJN<;\&
'H& NPGG8MTY& R<& @8Q<& ;AN:FJN<;& O@<& NPF=JHTF8OAJH& J=&
2
&
p
q
@
:
<
GKFJTAH?&JO@<M&NP9NOAOPO<;&OJFP<H<N&R<M<&<S8GAH<;&8N&R<FF\&
&
ꢀ
JR<Q<MY&O@<&M<8:OAJHN&=8AF<;&OJ&KMJ;P:<&O@<&;<NAM<;&KMJ;P:ON& !43,1/)98ꢀ4,ꢀ/39+7+89ꢀ
e$JM&;<O8AFNY&KF<8N<&N<<&O@<&#1'f\&
t
tBu
Bu
Ar
Na2S2O5
H
Ir(ppy)3, NaHCO3
S
2
@<M<&8M<&HJ&:JH=FA:ON&OJ&;<:F8M<\&
+
O
O
HO
DCE, 36 W CFL HO
Ar N2BF4
tBu 1b
1a (2.0 equiv)
tBu
2
3
J)034;1+*-+2+398ꢀ
3
3
3
3
3
3
q: Ar = 4-MeC6H4, 77% yield
t: Ar = C6H5, 57% yield
$
AH8H:A8F&NPKKJMO&=MJG&,8OAJH8F&,8OPM8F&1:A<H:<&$JPH;8OAJH&J=&
u: Ar = 4-MeOC6H4, 66% yield
t
!@AH8&e,JN\&potupnqu&8H;&posqpnnof&8H;&(A8H?NP&.MJQAH:<&)<T&
*89JM8OJMT& J=& $AH<& .<OMJ:@<GA:8F& #H?AH<<MAH?& e)$ounof& AN&
?
v: Ar = 4- BuC6H4, 62% yield
w: Ar = 4-FC6H4, 58% yield
x: Ar = 4-BrC6H4, 64% yield
M8O<=PFFT&8:EHJRF<;?<;\&
&
%
).+2+ꢀI?ꢀ+JM<&<S8GKF<N&=JM&O@<&M<8:OAJH&J=&rbG<O@TFbpYtb;AbC6ACb
$
49+8ꢀ'3*ꢀ7+,+7+3)+8ꢀ
9
POTFK@<HJF&G(ꢀ
pn
&
8N<;& JH& O@<& 89JQ<& M<NPFON& 8H;& KM<QAJPN& M<KJMONY & 8& o! &$ JM&N<F<:O<;&M<QA<RNY&N<<[&8f&V\&+AH8OOA&8H;&)\&+PIAUY&ꢀ96=L!/?4L!
.
.
6ELJ&pnnuY&ILY&oorpZ&9f&1\&0\&!@<GF<M&8H;&.\&ꢀ\&$PFF<MY&ꢀ96=L!/?4L!
6ELJ&pnnuY&ILY&oosqZ&:f&3\&)JOJQY&!\&!\&1:8M9JMJP?@&8H;&1\&1\&1O8@FY&
KJNNA9F<&G<:@8HANG&AHQJFQAH?&M8;A:8F&K8O@R8T&R8N&KMJKJN<;&
e1:@<G<& rf\& 'HAOA8FFTY& 8MTF& M8;A:8F& =MJG& 8MTF;A8UJHAPG&
O<OM8=FPJMJ9JM8O<&RJPF;&9<&=JMG<;&8NNANO<;&9T&O@<&<S:AO<;&
&
>?A8L!ꢀ96=LJ&pnnuY"ꢁLY&owon\&
p! 8f&+\&$<H?Y& \&28H?Y&1\&ꢀ\&*A8H?&8H;&5\&(A8H?Y&ꢀDAAL!0?@L!*65L!ꢀ96=\Y&
pnotY& GLY& opnnZ& 9f& )\& 28EAGAT8Y& 1\& 1@AH8GPM8Y& '\& -N8E8& 8H;& #\&
+AT8U8EAY&U5EL!*2C6ALJ!pnooY&HIY&rqruZ&:f&,\&1\&*AY&(\&)\&$M<;<MAEN<H&
NO8O<&J=&'MeKKTf
8KOPM<;& 9T& NPF=PM& ;AJSA;<Y& KMJQA;AH?& 8MTFNPF=JHTF& M8;A:8F&
AHO<MG<;A8O<\&'H&O@<&G<8HOAG<Y&K@<HJST&M8;A:8F& &RJPF;&9<&
<H<M8O<;&O@MJP?@&O@<&JSA;8OAJH&J=&K@<HJF&AH&O@<&KM<N<H:<&J=&8&
q
&PH;<M&qt&4&!$*\&2@<HY&O@AN&M8;A:8F&RJPF;&9<&
:
8
H;&(\&V\&.A::AMAFFAY&U44L!ꢀ96=L!.6B\Y&pnooY&ꢁꢁY&opsuZ&;f&(\&"M<RNY&
J
/
4:6>46Y&pnnnY&HNMY&owtn\&
?
9
q! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&7\&!@<HY&1\&*APY&4\&ꢀ8JY&%\&5PY&1\&4PY&(\&
A8JY& \&(A8H?Y&1\&48H?Y&1\&2P&8H;&%\&*AY&ꢀ96=L!/4:\Y&pnosYꢀLY&ttsrZ&9f&
8N<&QA8&8&NAH?F<&<F<:OMJH&OM8HN=<M&e1#2f\&1P9N<LP<HOFTY&O@<&
+
AHO<MGJF<:PF8M&@T;MJ?<H&8OJG&89NOM8:OAJH&9<OR<<H&K@<HJST&
M8;A:8F& &8H;&K@<HJF& &RJPF;OJ&J::PMY&?AQAH?&MAN<&OJ&9<HUTFA:&
M8;A:8F& \&2@<&8MTFNPF=JHTF&M8;A:8F&RJPF;&O@<H&:JG9AH<&RAO@&
<HUTFA:&M8;A:8F& &OJ&KMJ;P:<&O@<&:JMM<NKJH;AH?&KMJ;P:O& \&4<&
NNPG<;&O@8O&K@<HJFA:&M8;A:8F& &RJPF;&PH;<M?J&AHOM8GJF<:PF8M&
oYsbꢀ&N@A=O&R@<H&NP9NOM8O<&RAO@&8H&<O@TF&?MJPK&8OO8:@<;&JH&O@<&
6\&68H?Y&6\& 8JY&/\&%P8HY&/\&1PHY&7\&7@8&8H;&7\&48H?Y&%A66>!ꢀ96=\Y&
pnouY& GOY& oopZ& :f& 3\& )@8ETU8;<@Y& 6\& 48H?& 8H;& \& M<AOY& ꢀ96=L!
J
G
&
ꢀ
4
ꢀ
7
?==D>\Y!pnouY&KIY&rwttZ&;f&%\&!\&1<H8;AY& \&%PJY&4\&ꢀP&8H;&(\&
8H?Y&ꢀ96=L!ꢀ?==D>\Y&pnotY&KHY&ooronZ&<f&6\&48H?Y&*\&+8Y&+\&+8Y&
\&7@<H?Y&6\&1@8J&8H;&5\&48HY&,A8L!)6CC\Y&pnotY&GNY&snvpZ&=f&*\&7@<H?Y&
\&7@JPY&6\&ꢀ<Y&*\&*AY&(\&+8Y&6\&/APY&.\&7@JPY&5\&*APY&.\&5P&8H;&6\&*A8H?Y&'L!
9
8
I
J
,A8L!ꢀ96=LJ&pnotY&NGY&ttZ&?f&6\&7@PY& \&(A8H?Y&4\&ꢀ8JY&(\&/APY&(\&1PHY&"\&
48H?Y&.\&4<AY&V\&48H?Y&%\&*A&8H;&1\&2PY!,A8L!)6CC\Y&pnosY&GMY&tnuvZ&@f&
?
AC9?bKJNAOAJH&R8N&PN<;\&2@PN&O@<&NP9N<LP<HO&AHO<MGJF<:PF8M&
%
\&0JH?Y&(\&+8JY&ꢀ\&68HY&6\&7@<H?&8H;&%\&7@8H?Y&'L!,A8L!ꢀ96=LJ&pnosY&
@
T;MJ?<H&8OJG&89NOM8:OAJH&RJPF;&9<&AH@A9AO<;Y&F<8;AH?&OJ&8H&
NFY&rtwu\&
AH=<MAJM& M<NPFO\& $JM& O@<& :JGKJPH;N& RAO@& C6ACb9POTF& ?MJPK&
OO8:@<;&JH&O@<&?AC9?bKJNAOAJHY&O@<&AHOM8GJF<:PF8M&oYsbꢀ&N@A=O&
RJPF;&9<&@8GK<M<;&9T&O@<&NO<MA:&@AH;<M8H:<\&
r! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&5\&*APY&2\&!JH?Y&.\&*AP&8H;&.\&1PHY&,A8L!
8
:
?=?<L!ꢀ96=\Y&pnotY&GꢁY&wrotZ&9f&)\&1PHY&5\&!@<HY&5\&*AY&<O\&8F\&ꢀ96=L!
ꢀ?==D>\Y&pnosY!KGY&opoooZ&:f&ꢀ\&*A8H?Y&)\&(A8H?Y&4\&"AH?Y&6\&6P8HY&*\&
@P8AY&6\&!@<H&8H;&6\&4<AY&ꢀ96=L!ꢀ?==D>\Y&pnosY&KGY&otwpvZ&;f&5\&
1
R1
Ar
O
O
Ar N2BF4
Ir(III)*
*APY&5\&!@<H&8H;&(\&2\&+J@MY!,A8L!)6CC\Y&pnosY&GMY&qsupZ&<f&3\&.\&0<;;TY&
0\&/APY&2\&'R8N8EA&8H;&,\&)8G9<Y&,A8L! :?=?<L!ꢀ96=\Y&pnosY&GIY&tvnqZ&
=f&6\&5PY&.\&*APY&1\&*A&8H;&.\&1PHY&'L!,A8L!ꢀ96=\Y&pnosY&NFY&optwZ&?f&1\&
)8GADJY& +\& ꢀAMJO8Y& )\& 28JY& +\& 48O8H89<& 8H;& 2\& +PM8=PDAY&
06CA2965A?>!)6CC\Y&pnorY&KKY&sssoZ&@f& \&%<Y&"\&48H?Y&4\&"JH?Y&.\&+8Y&
6\&*A&8H;&6\&"AH?Y&06CA2965A?>!)6CC\YpnorY&KKY&srrqZ&Af&7\&4PY&ꢀ\&1JH?Y&
S
S
Ar
O
O
Ar
SO2
HO
3
R2
R1
Ir(IV)
H
O
O
1
HO
Ir(III)
S
Ar
R2
- H+
5
\&!PAY&!\&.AY&4\&"P&8H;&6\&4PY&,A8L!)6CC\Y&pnoqY&GKY&opunZ&Df&5\&7@8JY&#\&
R1
HO
intermolecular hydrogen
atom transfer
R1
O
H
"AGAOMAD<QA:&8H;&3\&+\&"JH?Y!'L!U=L!ꢀ96=L!/?4\Y&pnnwY&GIGY&qrtt\&
s! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&6\&*AY&2\&+A8JY&.\&*A&8H;&*\&48H?Y&,A8L!
)6CCLJ&pnovY&HFY&ouqsZ&9f&+\&ꢀP8H?Y&6\&7@PY&4\&ꢀ8JY&V\&48H?Y&"\&
48H?Y&$\&*APY&.\&4<AY&1\&2P&8H;& \&(A8H?Y&U5EL!/H>C9L!ꢀ2C2<\Y&pnouY&IKOY&
pppwZ&:f&(\&4<HY&4\&1@AY&$\&7@8H?Y&"\&*APY&1\&28H?Y&ꢀ\&48H?Y&5\&*AH&8H;&
V\&*<AY&,A8L!)6CCLJ&pnouY&GOY&qoqoZ&;f&(\&5PY&5\&6PY&(\&68H&8H;&/\&1JH?Y!
,A8L!)6CC\Y&pnouY&GOY&tpwpZ&<f&"\&68H?Y& \&ꢀP8H?Y&4\&4<AY&(\&*AY&%\&*AHY&
R2
R2
B
A
R1
R1
H
H
HO
HO
1
1
R2
R2
6
\&*APY&(\&"AH?Y&.\&1PH&8H;&ꢀ\&48H?Y&%A66>!ꢀ96=\Y&pnotY&GNY&stqnZ&=f&ꢀ\&
%
).+2+ꢀꢁ?&.F8PNA9F<&G<:@8HANG&&
2
@AN&DJPMH8F&AN&k&2@<&0JT8F&1J:A<OT&J=&!@<GANOMT&pnSS!
'L!+2=6\Y&pnoqY&FFY&obq&a&I&

ChemComm
Page 4 of 4
View Article Online
DOI: 10.1039/C8CC06567E
!
.+2!422&
#4:73'1ꢀ$'2+&
4
ꢀ
!
8H?Y&/\&*PY&!\&!@A8H?Y&6\&*PJY&(\&7@JPY&%\&48H?&8H;&V\&*<AY!U>86FL!
96=\!&>CL!#5\Y&pnotYꢀKKY&oZ&?f&%\&7@8H?Y&*\&7@8H?Y&ꢀ\&6AY&6\&*PJY&5\&/AY&
\&2PH?Y&*\&4P&8H;&V\&*<AY&ꢀ96=L!ꢀ?==D>\Y&pnotYꢀKHY&onrnu\&
1@8QHT8Y&)\&"\&ꢀ<NK&8H;&V\&1\&2N8AY&U5EL!/H>C9L!ꢀ2C2<LJ&pnovYꢀILFY&oZ&:f&
V\&1@8QHT8Y&1\& \&!J==<TY&)\&"\&ꢀ<NKY&1\&!\&0JNN&8H;&V\&1\&2N8AY&,A8L!
)6CCLJ&pnotY&GNY&svrvZ&;f&V\&0J;MB?P<U&8H;&4\&(\&+JM8HY&'L!,A8L!ꢀ96=LY&
pnotY&NGY&psrqZ&<f&4\&7@8H?&8H;&+\&*PJY&ꢀ96=L!ꢀ?==D>LJ&pnotY&KHY&
pwvnZ&=f&5\&+<H?Y&4\&7@8H?Y&7\&28HY&!\&"PY&!\&*AY&7\& JY&6\&*AY&5\&68H?Y&
+\&7@<HY&$\&(A8H?Y&(\&7@<H?Y&2\&48H?Y&*\&(A8H?Y&!\&1@P&8H;&!\&48H?Y!
ꢀ96=L!ꢀ?==D>LJ&pnopY&ꢁNY&rps\&
t! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&4\&4PY&1\&6AY&6\&6PY&4\&ꢀP8H?&8H;&ꢀ\&
A8H?Y&'L!,A8L!ꢀ96=\Y&pnouY&NHY&opprZ&9f&6\&48HY&(\&7@8H?Y&6\&!@<HY&*\&
JH?Y&$\&*PJ&8H;&%\&7@PY!,A8L! :?=?<L!ꢀ96=\Y&pnouY&GKY&upnrZ&:f&(\&*8AY&
\&!@8H?&8H;&%\&6P8HY&,A8L!)6CC\Y&pnotY&GNY&qowrZ&;f&V\&0J;MB?P<U&8H;&
(
)
*
4
\&(\&+JM8HY&'L!,A8L!ꢀ96=\Y&pnotY&NGY&psrqZ&<f&1\&ꢀ\&%PH;Y&0\&1\& or! $JM&N<F<:O<;&M<QA<RNY&N<<[&8f&%\&/AP&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>C\Y&
1
ꢀ
@<FE8M&8H;&(\&+\&,8?8ME8MY!./ꢀ!U5E\Y&pnosY&KY&tpwptZ&=f&5\&28H?Y&*\&
P8H?Y&6\&5PY&(\&68H?Y&4\&4P&8H;&ꢀ\&(A8H?Y!U>86FL!ꢀ96=\!&>CL!#5\Y&
pnosY&HY&otwZ&9f&ꢀ\&*AY& \&*A8&8H;&7\&1@AY&ꢀ2C2<L!/4:L!0649>?<LJ&pnooY&GY&
owoZ&:f&2\&,<R@JPN<&8H;&.\&1\& 8M8HY&U>86FL!ꢀ96=L!&>CL!#5\Y&pnooY&KFY&
qqtpZ&;f&-\& 8P;JAHY&ꢀ96=L!/?4L!.6E\Y&pnooY&ꢁFY&rwnpZ&<f&(\&0J9<MONJHY&
(\&.AFF8A&8H;&0\&)\&*PN@Y&ꢀ96=L!/?4L!.6ELJ&pnnoY&IFY&wr\&
pnorY&KIY&rpnsZ&?f&ꢀ\&*A&8H;&%\&*APY&'L!,A8L!ꢀ96=\Y&pnorY&MOY&snwZ&@f&6\&
PY&(\&7@8JY&5\&28H?Y&4\&4P&8H;&ꢀ\&(A8H?Y&U5EL!/H>C9L!ꢀ2C2<\Y&pnorY&
5
SꢁVY&pnpw\&
os! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&6\&7@PY&5\&!@<HY&!\&6P8HY&%\&*AY&(\&7@8H?&
8H;&6\&7@8JY&+2CL!ꢀ?==\Y&pnouY&NY&orwnrZ&9f&%\&*A8JY&5\&6AHY&)\&!@<HY&
/\&7@8H?Y&1\&7@8H?&8H;& \&1@AY&+2CL!ꢀ?==\Y&pnotY&MY&opwnoZ&:f&(\&(\&
2JK:U<RNEAY&.\&(\&!89M<M8Y&,\&'\&18K<M&8H;&+\&1\&18H=JM;Y&+2CDA6Y&pnotY&
KIGY&ppnZ&;f&$\&7@8H?Y&)\&ꢀJH?Y&2\&*AY&ꢀ\&.8ME&8H;&(\&6PY&/4:6>46Y&pnotY&
IKGY&pspZ&<f&.\&%8JY&4\&%PJY&(\&5P<Y&6\&7@8JY&6\&6P8HY&6\&5A8&8H;&7\&1@AY&
'L!U=L!ꢀ96=L!/?4\Y&pnosY&GIMY&oppqoZ&=f&(\&7@8H?Y&ꢀ\&!@<HY&!\&*AHY&7\&
*APY&!\&48H?&8H;&6\&7@8H?Y&'L!U=L!ꢀ96=L!/?4LJ&pnosY&GIMY&opwwnZ&?f&0\&
7@PY&(\&ꢀ<Y&5\&48H?&8H;&(\&6PY&'L!U=L!ꢀ96=L!/?4LJ&pnorY&GILY&oqowrZ&@f&
6\&VA@8M8&8H;&,\&!@8O8HAY&'L!U=L!ꢀ96=L!/?4LY&pnorY&GILY&vwvZ&Af&/\&%PY&
ꢀ\&ꢀ\&VF&+8G8MAY&)\&%M8:UTEY&#\&"A<MN&8H;&*\&V:E<MG8HHY&U>86FL!
ꢀ96=L!&>CL!#5\Y&pnorY&KIY&qvtvZ&Df&"\&1@898N@JQ&8H;&-\&"8P?PFANY&'L!
U=L!ꢀ96=L!/?4LJ&pnonY!GIHY&qwtsZ&Ef&1\&*AHY&!\&1JH?Y&%\&!8AY&4\&48H?&
8H;&7\&1@AY&'L!U=L!ꢀ96=L!/?4\Y&pnnvY&GIFY&opwnoZ&Ff&5\&!@<HY&!\&#\&
%JJ;@P<&8H;&(\&6PY&'L!U=L!ꢀ96=L!/?4\Y&pnntY&GHNY&optqrZ&Gf&3\&%\&
78AON<QY&"\&1@898N@JQ&8H;&-\&"8P?PFANY&'L!U=L!ꢀ96=L!/?4\Y&pnnsY&GHMY&
oqosrZ&Hf&*\&3\&"<N8AY&)\&*\&ꢀPFF&8H;&+\&1\&18H=JM;Y&'L!U=L!ꢀ96=L!/?4LJ&
pnnrY&GHLY&wsrp\&
u! &$JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&4\&*AY&+\& <FF<M&8H;&5\&4PY&ꢀ96=L!
ꢀ
'
?==D>\Y&pnorY&KFY&wsoqZ&9f&*\&+8F<Ob18HUY&(\&+8;MU8EY&1\&3\&*<T&8H;&
\&0\& 8S<H;8F<Y&,A8L! :?=?<L!ꢀ96=\Y&pnonY&NY&sqprZ&:f&.\&(\&ꢀJ?8H&8H;&
&%\&!JSY&,A8L!-A?46BB!.6BL!"6E\Y&pnnwY&GIY&vusZ&;f&0\&+\&4AFNJH&8H;&
\&4\&4PH;<MFTY&'L!U=L!ꢀ96=L!/?4\Y&owurY&OLY&uqsn\&
\
1
v! 8f&%\&/APY&)\&7@JPY&*\&%8J&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnovY&KY&twoZ&
&
9
f&)\&ꢀJ=G8HY ,\&*AP&8H;&%\&+8HJFAE8E<NY&ꢀ96=L!#DAL!'LJ&pnovY&HꢁY&
oovspZ&:f&"\&7@<H?Y&(\&4PY&^/D<7DA!":?G:56!&>B6AC:?>!.624C:?>B!7?A!
A82>:4!/H>C96B:B_Y&,8OPM<&1KMAH?<M[& <MFAHY&pnouZ&;f&%\&*APY&!\&$8H&
H;&(\&4PY&,A8L! :?=?<L!ꢀ96=LJ!pnosY&GIY&oswpZ&<f&#\&(\&#GG<OO&8H;&
\&!\&4AFFANY&UB:2>!'L!,A8L!ꢀ96=LJ&pnosY&ꢁY&tnpZ&=f&V\&1\&"<<GAH?Y&#\&(\&
GG<OOY&!\&1\&0A:@8M;Nb28TFJM&8H;&+\&!\&4AFFANY&/H>C96B:BY&pnorY&ꢁLY&
,
8
+
#
punoZ&?f&.\& ANN<M<O&8H;&,\& F8H:@8M;Y&,A8L! :?=?<L!ꢀ96=LJ&pnoqY&GGY&
sqwq\&
w! .\&1\&18HOJN&8H;&+\&2\&1\&+<FFJY&'L!*?<L!/CAD4LJ!owvvY&GMNY&opo\&
on! $JM& M<:<HO& N<F<:O<;& <S8GKF<NY& N<<[& 8f& ,\& QJH& 4JF==Y& (\& !@8MY& 5\&
$
*
:
*
MJ?H<PS&8H;&2\&!8HO8OY&U>86F\&ꢀ96=\&&>C\&#5\Y&pnouYꢀKLY&stotZ&9f&,\&
APY1\&*A8H?&8H;&%\&+8HJFAE8E<NY&U5EL!/H>C9L!ꢀ2C2<LJ&pnouY&IKOY&oqnvZ& ot! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&4\&1@P&8H;&!\&,<Q8;JY&U>86FL!ꢀ96=L!
f&0\&+8JY&7\&6P8HY&6\&*A&8H;&(\&4PY&ꢀ96=L!#DAL!'LJ&pnouY&HIY&voutZ&;f&$\&
APY&(\&48H?Y&.\&7@JPY&%\&*AY&4\&ꢀ8JY&1\&2P&8H;& \&(A8H?Y&U>86FL!ꢀ96=L!
&
&>CL!#5LJ&pnouY&KLY&ovvoZ&9f&(\&7@8H?Y&6\&*AY&$\&7@8H?Y&!\&ꢀP&8H;&6\&!@<HY&
U>86FL!ꢀ96=L!&>CL!#5LJ&pnotY&KKY&ovupZ&:f&(\&!\&!@P&8H;&2\&0JQANY&
+2CDA6Y&pnotY&KIOY&pupZ&;f&%\&(\&!@JAFY&/\&7@PY&"\&!\&+AFF<MY&!\&(\&%P&
8H;&0\&0\&)HJRF<NY&+2CDA6Y&pnotY&KIOY&ptvZ&<f&!\&48H?Y&)\&ꢀ8MGN&8H;&
#\&+<??<MNY&U>86FL!ꢀ96=L!&>CL!#5LJ&pnotY&KKY&oqrwsZ&=f&(\&*\&(<>M<TY&(\&
V\&2<MM<OO&8H;&"\&4\&!\&+8:+AFF8HY&/4:6>46Y&pnosY&IꢁOY&osqpZ&?f&/\&
/AH&8H;&1\&6PY&,A8L!)6CCLJ&pnosY&GMY&ovwrZ&@f&*\&(\&VFF<HY&.\&(\&!89M<M8Y&
+\&*<<&8H;&+\&1\&18H=JM;Y&'L!U=L!ꢀ96=L!/?4\Y&pnorY&GILY&stnuZ&Af&V\&
,J9F<&8H;&"\&4\&!\&+8:+AFF8HY&'L!U=L!ꢀ96=L!/?4LJ&pnorY&GILY&ootnpZ&Df&
4\&*APY&5\&ꢀP8H?Y&+\&!@<H?Y&0\&(\&,A<FN<HY&4\&V\&%J;;8M;&'''&8H;&(\&2\&
%MJQ<NY&/4:6>46Y&pnopY&IIMY&oqppZ&Ef&(\&+\&+8T<MY&U44L!ꢀ96=L!.6BLJ&
pnooY&ꢁꢁY&qtZ&Ff&+\&1\&!@<H&8H;&+\&!\&4@AO<Y&/4:6>46Y&pnonY&IHMY&sttZ&
Gf&1\&2NPHJAY&'\&0TPY&2\&-EP;8Y&+\&28H8E8Y&+\&)JG8ONP&8H;&,\&1JHJ;8Y&
'L!U=L!ꢀ96=L!/?4LJ&owwvY&GHFY&vtwp\&
&
>CL!#5LY&pnouY&KLY&ossunZ&<f&ꢀ\&48H?Y&1\&1PH&8H;&(\&!@<H?Y&,A8L!)6CC\Y&
pnouY!GOY&svrrZ&=f&ꢀ\&)JHAN@AY&ꢀ\&28H8E8&8H;&)\&+8H89<Y&,A8L!)6CC\Y&
pnouY&GOY&osuvZ&?f&(\&1@<H?Y&6\&*A&8H;&%\&/APY&,A8L!ꢀ96=L!$A?>CLJ&pnouY!
ꢁ
)
Y&wsZ&@f&6\&5A8H?Y&6\&)P8H?&8H;&(\&4PY&ꢀ96=L!#DAL!'LJ&pnouY&HIY&twwtZ&Af&
\&7@JPY&ꢀ\&5A8&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnotY&IY&vtsZ&Df&"\&7@<H?Y&
+
"
4
\&!@<HY&*\&68J&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnotYꢀIY&wvsZ&Ef&0\&+8JY&
\&7@<H?Y&ꢀ\&5A8&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnotY&IY&twqZ&Ff&5\&
8H?Y&*\&5P<&8H;&7\&48H?Y&,A8L!)6CCLJ&pnorY&GLY&rnstZ&Gf&"\&7@<H?Y&6\&
VHY&7\&*A&8H;&(\&4PY&U>86FL!ꢀ96=L!&>CL!#5LJ!pnorY&KIY&prso\&
oo! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&7\&1@<HY&6\&4PY&!\&ꢀ<Y&*\&ꢀ<Y&4\&ꢀ8JY&V\&
4
8H?Y&1\&2P&8H;& \&(A8H?Y&ꢀ96=L!ꢀ?==D>\Y&pnovY&KꢁY&rrsZ&9f&6\&48H?Y&
*
\&"<H?Y&(\&7@JPY&5\&48H?Y&ꢀ\&+<AY&(\&ꢀ8H&8H;&6\&.8HY&U5EL!/H>C9L!
ꢀ
+
2C2<LY&pnovYꢀILFY&ontnZ&:f&6\&!@<HY&.\&0\&"\&+PMM8TY&V\&2\&"8QA<N&8H;& ou! 8f&)\&7@JPY&(\&7@8H?Y&*\&*8AY&(\&!@<H?Y&(\&1PH&8H;&(\&4PY& ꢀ96=L!
&
&
&
&
\&!\&4AFFANY!'L!U=L!ꢀ96=L!/?4LY&pnovY&GꢁFY&vuvoZ&;f&2\&*APY&"\&7@<H?Y&7\&
ꢀ?==D>LJ&pnovY&KꢁY&urswZ&9f&"\&68H?Y .\&1PHY 4\&4<AY $\&*APY ꢀ\&
7@8H?&8H;&ꢀ\&48H?Y&ꢀ96=L!#DAL!'LJ&pnovY&HꢁY&rrpqZ&:f&ꢀ\&5A8Y&6\&VHY&5\&
7<H?&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnovY&KY&qttZ&;f&2\&*APY&4\&7@JP&
8H;&(\&4PY&,A8L!)6CCLJ!pnouY&GOY&ttqvZ&<f&ꢀ\&5A8Y&6\&VHY&5\&7<H?&8H;&(\&
4PY&ꢀ96=L!ꢀ?==D>LJ!pnouY&KIY&opsrvZ&=f&6\&*AY&0\&+8J&8H;&(\&4PY&
,A8L!)6CCLJ!pnouY&GOY&rrupZ&?f&1\&6<Y&ꢀ\&48H?Y&/\&5A8JY&/\&"AH?&8H;&(\&
4PY&U5EL!/H>C9L!ꢀ2C2<LJ&pnorY&IKLY&qppsZ&@f&)\&7@JPY&+\&!@<HY&*\&68J&
8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnovY&KY&quoZ&Af&)\&48H?Y&%\&48H?Y&%\&
"P8H&8H;&!\&5A8Y&./ꢀ!U5ELY&pnouY!MY&soqoq\&
*
A&8H;&(\&4PY&U5EL!/H>C9L!ꢀ2C2<LJ!pnovY&ILFY&vtsZ&<f&(\&7@8H?Y&$\&7@8H?Y&
*
\&*8AY&(\&!@<H?Y&(\&1PH&8H;&(\&4PY!ꢀ96=L!ꢀ?==D>LJ!pnovY&KꢁY&qvwoZ&=f&
(
2
\&7@8H?Y&)\&7@JP&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ&pnovY&KY&voqZ&@f&V\&*\&
MA99TY&'\&0J;MB?P<UY&1\&1@8MA==P;AH&8H;&,\&"\& 8FFY&'L!,A8L!ꢀ96=LJ&pnouY&
NHY&ppwrZ&Af&V\&1\&"<<GAH?Y&!\&(\&0PNN<FF&8H;&+\&!\&4AFFANY&U>86FL!
ꢀ
0
snv\&
96=L!&>CL!#5LJ!pnotY!KKY&uruZ&Df&V\&1\&2N8AY&(\&+\&!PMOJY& \&,\&0J:E<Y&V\&
\&"<:@<MOb1:@GAOOY&%\&)\&'H?F<&8H;&3\&+8N:AOOAY&,A8L!)6CCLJ&pnotY&GNY&
op! 8f&(\&7@8H?Y&6\&VH&8H;&(\&4PY&ꢀ96=L!#DAL!'\Y&pnouY&HIY&wruuZ&9f&6\& ov! 6\&*AY&0\&+8J&8H;&(\&4PY&,A8L!)6CCLJ!pnouY&GOY&rrup\&
8H?Y& \&"PY&4\&1@8Y&ꢀ\&+<AY&(\&ꢀ8H&8H;&6\&.8HY&,A8L!ꢀ96=L!$A?>C\Y& ow! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&$\&7@8H?Y&"\&7@<H?Y&*\&*8AY&(\&!@<H?Y&(\&
4
pnouY&ꢁY&oqoqZ&:f&,\&*APY&1\&*A8H?&8H;&%\&+8HJFAE8E<NY&U5EL!/H>C9L!
1PH&8H;&(\&4PY&,A8L!)6CCLJ!pnovY&HFY&ootuZ&9f&2\&*APY&6\&*AY&*\&*8AY&(\&
!@<H?Y&(\&1PH&8H;&(\&4PY&,A8L!)6CCLJ!pnovY&HFY&qtnsZ&:f&(\&7@8H?Y&)\&
7@JP&8H;&(\&4PY&,A8L!ꢀ96=L!$A?>CLJ!pnovY&KY&voqZ&;f&"\&7@<H?Y&(\&6P&
8H;&(\&4PY&U>86FL!ꢀ96=LJ!&>CL!#5LJ!pnotY&KKY&oowps\&
ꢀ
ꢁ
2C2<\Y&pnouY&IKOY&oqnv\&;f&1\&6<&8H;&(\&4PJ!ꢀ96=L!ꢀ?==D>\Y&pnopY&
NY&onnquZ&<f&+\&48H?Y&1\&!@<H&8H;&5\&(A8H?Y&,A8L!)6CC\Y&pnouY&GOY&
rwotZ&=f&ꢀ\&)JHAN@AY&ꢀ\&28H8E8&8H;&)\&+8H89<Y&,A8L!)6CC\Y&pnouY&GOY&
osuvZ&?f&V\&1@8QHT8Y&)\&"\&ꢀ<NKY&3\&+8N:AOOA&8H;&V\&!\&1GAO@Y&U>86FL! pn! $JM&N<F<:O<;&<S8GKF<NY&N<<[&8f&/\&4PY&%\&VJ&8H;&$\&*APY&,A8L!ꢀ96=L!
ꢀ
1
4
96=L!&>CL!#5\Y&pnosY&KꢁY&oqsuoZ&@f&V\&1@8QHT8Y&1\& \&!J==<TY&V\&!\&
GAO@&8H;&3\&+8N:AOOAY&,A8L!)6CC\Y&pnoqY&GKY&tpptZ&Af&+\&4\&(J@HNJHY&1\&
\& 8?F<TY&,\&.\&+8HE8;Y&0\&%\& <M?G8HY&3\&+8N:AOOA&8H;&$\&"\&2JNO<Y&
$A?>CLJ&"-'[&on\onqw`:vLJnnrpv<Z&9f&2\&*APY&(\&*APY&1\&5A8Y&(\&+<H?Y&5\&
1@<HY&5\&7@PY&4\&!@<HY&!\&1PH&8H;&$\&!@<H?Y&Uꢀ/!,=682J&pnovY&IY&
ornwZ&:f&4\&68H?Y&.\&"8AY&)\&*PJ&8H;&*\&4PY&U5EL!/H>C9L!ꢀ2C2<\Y&pnotY!
IKNY&qovrZ&;f&ꢀ\&#?8GAY&2\&';<Y&6\&)8R8OJ&8H;&6\&ꢀ8G8N@AG8Y&ꢀ96=L!
ꢀ?==D>\Y&pnosY&KGY&ottusZ&<f&V\&.MJEJ=A<Q8Y&V\&'\&.MAE@J;]EJY&1\&
"<:@<MO&8H;&$\&+<T<MY&ꢀ96=L!ꢀ?==D>\Y&pnnvY&onns\&
U>86FL!ꢀ96=L!&>CL!#5\Y&pnorY&KIY&rrnr\&
oq! $JM&N<F<:O<;&M<8:OAJHN&AHQJFQAH?&MJH?8FAO<Y&N<<[&8f&2\&7@8JY&6\&*AY&6\&
7
@8H?Y&6\&4P&8H;&5\&ꢀPY&"-'[&on\onpo`8:NNPN:@<G<H?\v9npovpZ&9f&V\&
ꢁ
&a&'L!+2=6\Y&pnopY&FFY&obq&
2@AN&DJPMH8F&AN&k&2@<&0JT8F&1J:A<OT&J=&!@<GANOMT&pnSS&