Gold catalysis: Biarylphosphine ligands as key for the synthesis of dihydroisocoumarins

Article abstract of DOI:10.1071/CH13552

Agold-catalyzed phenol synthesis was successfully used in the synthesis of dihydroisocoumarins for the first time.Alarge number of gold(I) complexes were prepared and tested; only complexes based on the biarylphosphine motif were successful. CSIRO 2014.

Full text of DOI:10.1071/CH13552

RESEARCH FRONT
CSIRO PUBLISHING
Aust. J. Chem. 2014, 67, 481–499
Full Paper
http://dx.doi.org/10.1071/CH13552
Gold Catalysis: Biarylphosphine Ligands as Key
for the Synthesis of Dihydroisocoumarins
A B D
, ,
A
A
A. Stephen K. Hashmi,
Benjamin Bechem, Annette Loos,
A
A
C
Melissa Hamzic, Frank Rominger, and Hassan Rabaa
A
Organisch-Chemisches Institut, Ruprecht-Karls-Universitat Heidelberg,
¨
Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
B
Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589,
Saudi Arabia.
C
Universite´ Ibn Tofail, LCTA, De´partement de Chimie, PO Box 133, Ke´nitra 14000,
Morocco.
D
Corresponding author. Email: hashmi@hashmi.de
A gold-catalyzed phenol synthesis was successfully used in the synthesis of dihydroisocoumarins for the first time. A large
number of gold(I) complexes were prepared and tested; only complexes based on the biarylphosphine motif were
successful.
Manuscript received: 11 October 2013.
Manuscript accepted: 29 January 2014.
Published online: 27 February 2014.
Introduction
The western part looks like an ideal target for gold-catalyzed
phenol synthesis, but all initial efforts to form the dihydroiso-
coumarin skeleton with the gold catalysts usually used in phenol
synthesis failed.[45]
The gold-catalyzed synthesis of phenols[1–24] (Scheme 1) has
proved to be an excellent tool for the synthesis of benzoanellated
carbo- and heterocycles 2 from easily available substrates 1 and
is probably one of the most reliable gold-catalyzed organic
reactions with a broad scope.[25–36] The positioning of the
hydroxyl group ortho to the anellation point is difficult to
achieve by classical anellation strategies, which usually direct
an intramolecular electrophile to the para and not to the ortho
position of the phenolic hydroxyl group. Depending on
the length of the tether, both benzo-anellated five- and six-
membered rings can be prepared.
Dihydroisocoumarin natural products are interesting targets;
along with examples like mellein,[37] phyllodulcin,[37] hydran-
genol,[37] ochratoxin B,[38]] amicoumacin C,[39] gamahorin,[40]
in the last decade ajudazol A has been a prominent target.
Ajudazol A is an antimicrobial compound from myxobacteria
Chondromyces crocatus that inhibits mitochondrial electron
transport. It was first isolated by Ho¨fele et al.[41] The eastern
part of the molecule has already been synthesized by Taylor
et al. (C12–C28)[42] and Rizzacasa et al. (C9–C29)[43] (Fig. 1);
biosynthesis has been investigated by Mu¨ller et al.[44]
Recently, a synthesis of the core of the western part of
Ajudazol A was published by Marquez et al.[46a] and the total
synthesis was reported by Menche.[46b] This has prompted us to
disclose our efforts in the development of a methodology for the
part of the natural product that is of general interest for that type
of building block. We report here that only gold(I) phosphine
complexes with a biaryl substituent on phosphorus efficiently
catalyze phenol synthesis to the dihydroisocoumarin skeleton,
one more potential application of gold catalysis in total
synthesis.[47]
Results and Discussion
The synthesis of the 1,7-enyne substructure of the substrates for
gold catalysis begins with the regioselective ring-opening of
the epoxides 4 with lithiated 2-methylfuran 3. This delivers the
furylethanols 5 (Table 1).
Thenext step was the synthesisof the propiolic acid esters. The
alcohols 5 were coupled with propiolic acid using di(cyclohexyl)
R3
R3
R4
R2
R1
R4
X
X ꢀ O, OCR2, NR, CR2NR, CR2, ...
R2
R1
R1 ꢀ H, alkyl, aryl, alkynyl
[Au]
R2 ꢀ H, alkyl, Br
X
O
Phenol
synthesis
R3 ꢀ H, alkyl
H
R5
R5
R4, R5 ꢀ H, alkyl, aryl
OH
1
2
Scheme 1. The gold-catalysed phenol synthesis; the enyne substructure is shown in bold.
Journal compilation Ó CSIRO 2014
www.publish.csiro.au/journals/ajc

482
A. S. K. Hashmi et al.
O
O
OH
O
O
O
OH
O
OH
O
OH
O
Mellein
Phyllodulcin
Hydrangenol
O
O
O
O
H
N
H
O
O
O
HO
N
H
O
OH
O
OH
OH
O
OH
Ph
OH
O
Ochratoxin B
Amicoumacin C
Gamahorin
28
N
OMe
OH
O
O
29
N
9
12
O
Ajudazol A
O
OH
Western part
Eastern part
Fig. 1. Dihydroisocoumarine-substructures in natural products.
Table 2. Esterification of alcohols 5 with propiolic acid
Table 1. Epoxide opening with lithiated 2-methylfuran
R1
R1
R1
DCC/DMAP
or Ph3P/DEAD
(1) nBuLi, THF
OH
O
OH
0ꢁC, 24 h
Propiolic acid
THF
O
O
O
O
R2
R2
O
R2
R1
O
5
6
5
(2)
3
4
Entry
R1 in 5
R2 in 5
Product (yield)
R2
1
2
3
4
5
6
7
8
Me
H
6a (16 %)
6b (25 or 58 %A)
Entry
R1 in 4
R2 in 4
Product (yield)
Pr
H
Bu
H
6c (30 %)
6c (86 %)A
6d (29 %)
1
2
3
4
5
6
7
8
Me
H
5a (67 %)
5b (34 %)
5c (45 %)
5d (42 %)
5e (42 %)
5f (43 %)
5g (9 %)
–
Bu
H
Pr
H
Ph
H
Bu
H
CH2-OPh
H
6e (25 %)
6f (17 or 39 %A)
Ph
H
CH2-(2-methylfuryl)
Ph
H
CH2-OPh
H
CH2OH
6g (57 %)
CH2-(2-methylfuryl)
Ph
H
AObtained by Mitsunobu coupling.
CH2OH
H
4-NO2C6H4
THT
HAuCl4 ꢂ 2H2O
THT Au
Cl
EtOH/H2O
RR1R2P
carbodiimide (DCC)/4-N,N-dimethylaminopyridine (DMAP)
(Table 2). The alternative Mitsunobu coupling turned out to
be more efficient.
RR1R2P
Au
Cl
THT Au
Cl
DCM
–THT
For this investigation, a series of different gold(I) complexes
was prepared by the normal route for the synthesis of these
compounds: formation of tetrahydrothiophengold(I) chloride
from tetraauric acid and subsequent ligand exchange with
phosphine ligands (Scheme 2). For the catalysis reactions, these
complexes were converted into the catalytically active cationic
form by the addition of the corresponding silver salt (Scheme 2).
AgX
ꢃ
ꢄ
RR1R2P
RR1R2P
Au
Cl
ꢂ
Au
–AgCl
Scheme 2. General synthesis of gold phosphine complexes (THT, tetra-
hydrothiophen) and activation of gold phosphine complexes by silver salts.

Coumarins
483
The six different complexes prepared initially are shown in
substitutent on the phosphine, the difference between the
unsubstituted biaryl system in Au-BiarylB (entry 1) and the
methyl-substituted biaryl system in Au-BiarylL (entries 2 and 3)
is less significant than with the cyclohexyl substituent on the
phosphine. The other donor substitutents are also not as benefi-
cial as those shown in Table 6; the dimethylamino group in
Au-BiarylM (entry 4) and the isopropyl groups in Au-BiarylN
(entry 5) show reduced yields only. The binaphthyl group in
Au-BiarylO (entries 6 and 7), however, gives yields similar to
entries 1–3.
Now it was also interesting to compare the phosphines with
available identical biaryl units that had different substituents on
phosphorous, which was the case for the dimethylamino group.
In Table 8, these are compared: it is obvious that the dicyclo-
hexyl derivative is most active (entry 1), the di-tert-butyl
derivative significantly less active (entry 2), and the phenyl
group is inactive (entry 3).
Table 3; four of these could be characterized by X-ray structure
analyses.[48] Au-PhosphineB with the butyl cataCXium ligand
in the crystal shows a disordering of the butyl side chain and
close contact of gold and nitrogen. Au-PhosphineC during the
crystallization process delivers Au-PhosphineC2 with two phos-
phine ligands on gold; the chloride is not coordinated to the gold
centre. The benzyl cataCXium ligand in Au-PhosphineD does
not show disorder similar to Au-PhosphineB, the benzyl group
occupying a defined position in the crystals. Au-BiarylA like
Au-PhosphineB also shows a gold–nitrogen contact and the
distal aryl group of the biaryl unit is close to the gold centre.
Having the substrates 6 and the catalysts Au-PhosphineA–
Au-PhosphineD, Au-BiarylA and Au-BiarylB at hand, we now
could finally investigate the essential point, the cycloisomeriza-
tion of 6 to dihydroisocoumarins. For the initial catalyst screen-
ing, we used substrate 6c. As observed previously,[45] the
formation of dihydroisocoumarins is a challenge in the field of
gold-catalyzed phenol synthesis. Simple gold complexes like
AuCl3 and AuCl (Table 4, entries 1–4), which usually show at
least some activity, were completely inactive even at tempera-
tures up to 708C; the starting material was recovered. The same
was true for most of the gold(I) phosphine complexes; this
applied for both the preformed catalysts with the bis(triflour-
omethylsulfonyl)imide (NTfꢀ2 ) counter ion and for in situ
activated gold(I) complexes, in both dichloromethane and ace-
tonitrile (entries 5–13). With the biaryl ligand in a complex with
the weakly coordinating NTfꢀ2 counter ion (Au-Biaryl A), we
observed traces of the product (entry 15), but only in dichlor-
omethane and not in acetonitrile (entry 14). We were delighted
to see that Au-BiarylB in situ after activation with the non-
coordinating BFꢀ4 counter ion, when going from room tempera-
ture to 708C, delivered a 50 % yield of the desired product (entry
17). Again, in acetonitrile the same system showed no conver-
sion (entry 16). This could even be slightly improved to 57 %
when the reaction was done at 258C, where it was slower
(entry 20). Again, in acetonitrile the same system showed no
conversion (entry 16). THF also inhibited the reaction and
starting at 708C immediately led to decomposition of the catalyst
(entry 18). Buchwald-type biaryl ligands have received increas-
ing interest in gold-catalyzed reactions. The number of publica-
tions where Au-biaryl complexes play a substantial role in either
reactivity or selectivity is continually growing.[49]
Next we explored the influence of a pyrrole subunit in the
biaryl moiety. Table 9 shows two such catalysts. These show
some activity and completely converted the substrate 6c, but the
1
in situ H NMR spectra showed mainly polymerization; only
low yields were obtained with both pyrrole-based catalysts. This
once more underlines the difficulties that can be observed
with this class of substrates and the unique advantages of
catalysts like Au-BiarylC, which efficiently convert 6c into
the dihydroisocoumarin 7c.
As Au-BiarylC was the best catalyst, we used this complex
for the conversion of the other substrates. Table 10 shows the
results obtained with the substrates 6a–6g. Whereas the alkyl-
substituted 6a–6c gave quite comparable yields of 7a–7c
(entries 1–3), with 6d–6f, only reduced amounts of 7d–7f
(entries 4–6) were formed. The disubstituted 6g with a free
hydroxy group failed to be converted.
The structures of the synthetic intermediate 5e, the substrate
6e, and the product 7e were unambiguously proved by crystal
structure analyses (Fig. 2).[48] In the solid-state structure of 7e, a
hydrogen bond between the phenolic hydroxy group and the
ester carbonyl group is visible, probably a typical feature of the
whole family of these products.
From efforts to prepare the cationic variant of the Au-BiarylF
catalyst by addition of silver tetrafluoroborate, we isolated some
material that separated by spontaneous crystallization. Crystal
structure analysis showed that both dimethylamino groups are
protonated and that this dinuclear complex, Au-BiarylS, con-
nects two gold(I) centres by a chloro bridge (Fig. 3).[48] The
charge is compensated for by BFꢀ4 units in the crystal lattice.
Typical bond lengths and bond angles are shown in Table 11.
The coordination geometry at both gold centres is almost linear;
the two gold centres are quite close, the Au–Cl–Au angle being
only 868. The other values are normal; only the short contact
distance between the plane of the distal ring of the biaryl unit
and the gold centre is remarkable.
Based on the success of the biarylphosphine ligands, 16
different complexes containing the biaryl motif were prepared
by the methods mentioned above. These are shown in Table 5;
12 of these complexes could even be characterized by X-ray
structure analysis.[48]
These Buchwald-type biaryl ligands were tested in the reac-
tion of 6c. The results obtained with the biaryl-biscyclohexyl
phosphines are shown in Table 6. The unsubstituted Au-BiarylD
gave a decent yield of 7c, at both 508C and at room temperature
(entries 1 and 2). With the methyl-substituted Au-BiarylE, a
slightly better yield of 7c was obtained (entry 3). With stronger
donors in the same position of the biaryl unit, like the dimethy-
lamino group in Au-BiarylF (entry 4), the dimethoxy derivative
Au-BiarylG (entry 5), the di(isopropoxy) derivative Au-BiarylH
(entry 6) or the tri(isopropyl) derivative Au-BiarylI (entry 7), no
improvement was achieved. However, acceptors on the biaryl
unit, as in Au-BiarylJ (entry 8) and Au-BiarylK (entry 9), led to a
complete failure to catalyze this reaction. The highly substituted
Au-BiarylC (entry 10) gave the best results.
In explaining the unusual reactivity of the Au-Biaryl cata-
lysts, this short gold–arene contact may be the key. In addition to
related work of Gray,[50,51] we started a theoretical investigation
of the geometries and the resulting reactivity effects of these
complexes.[52] Initial calculations nicely confirm the structural
features of Au-BiarylF (see Supplementary Material), but
significantly more work is necessary to understand the quite
short arene–gold contact and its impact on catalyst activity.
In Fig. 4, the molecular structures obtained from the X-ray
crystal structure analysis ofAu-BiarylC, D, E, F, G, H, I, M, N, O,
Q, and R are superimposed. The structural characteristics match
the analogous complexes described in the literature.[50,51,53]
Turning to the biaryl-bis-tert-butyl phosphines in Table 7, we
used the same substrate to allow comparison. With the tert-butyl

484
A. S. K. Hashmi et al.
Table 3. Gold(I) phosphine complexes used in this investigation
Entry
Structure
X-ray structure analysis
ꢃ
ꢄ
OTs
P
Au
1
Au-PhosphineA
F3
C1
F2
ꢃ
ꢄ
nBu
P
NTf2
F1
O2
Au
O1
S1
S2
Au1 N1
P1
2
O3
O4
F5
C2
F6
Au-PhosphineB
F4
tBu
P
Au1
P2
tBu
Au
P1
Cl1
Cl
tBu
3
Au-PhosphineC
Au-PhosphineC2
Bz
P
Au Cl
P1
4
Au1
Au-PhosphineD
Cl1
F6
F5
F4
C22
ꢃ
ꢄ
NTf2
O1
tBu
tBu
C5
P
Au
C7
C6
S1
O4
O2
5
N1
S2
C1
P1 Au1
O3
C2
C21
F1
F2
Au-BiarylA
F3
–
tBu
tBu
P
Au
Cl
6
Au-BiarylB

Coumarins
485
Table 4. Catalyst development stage 1 general catalyst screening
]
CD3CN, acetonitrile-D3; CD2Cl2, dichloromethane-D2; AgNTf2 , silver(I) bis(trifluormethansulfon)imide
Bu
Bu
[Au], 5 mol-%
O
O
O
DCM
O
6c
OH
Solvent
O
7c
Entry
Catalyst
Additive
Temperature [8C]A
Yield of 7cB
1
5 mol-% AuCl3
–
–
CDCN
CDCN
CDCN
CDCl
CDCl
CDCl
CDCl
CDCl
CDCN
CDCl
CDCN
CDCl
CDCN
CDCN
CDCl
CDCN
CDCl
CDCl
d8-THF
CDCl
25–70
25–70
25–70
25–70
25–70
25–70
25
–
2
10 mol-% AuCl3
–
3
10 mol %AuCl3
10 mol-% BF3OEt2
–
4
5 mol-% AuCl
5 mol-% AgBF4
–
5
5 mol-% Au-PhosphineA
5 mol-% Au-PhosphineB
5 mol-% Au-PhosphineB
5 mol-% Au-PhosphineB
5 mol-% Au-PhosphineB
5 mol-% Au-PhosphineC
5 mol-% Au-PhosphineC
5 mol-% Au-PhosphineD
5 mol-% Au-PhosphineD
5 mol-% Au-BiarylA
5 mol-% Au-BiarylA
5 mol-% Au-BiarylB
5 mol-% Au-BiarylB
5 mol-% Au-BiarylB
5 mol-% Au-BiarylB
5 mol-% Au-BiarylB
5 mol-% AgNTf2
–
6
–
–
7
–
–
8
–
70
–
9
–
25–70
25–70
25–70
25–70
25–70
25–70
25–70
25–70
25–70
70
–
10
11
12
13
14
15
16
17
18
19
20
AgBF4
AgBF4
AgBF4
AgBF4
–
–
–
–
–
–
–
traces
–
AgBF4
AgBF4
AgBF4
AgBF4
AgBF4
50 %
–
70
–
25
57 %
A25–708C: the temperature was increased stepwise, first to 308C and then in steps of 108C.
BYield by 1H NMR integration.
In the plot, the second aryl group of the Buchwald ligand is
fixed for superimposition of the structures and the variety of
flexible side arms with the P–Au–Cl unit is demonstrated. The
general motif comprises the almost-linear coordination of the
AuI atom to the chloride and the phosphorus atom of the ligand.
The second feature consists of the AuI–p arene interaction with
the coordinating aryl moiety of the Buchwald ligand. Aurophilic
interactions are not present owing to the fact that the Au–Au
distance for any complex is larger than the corresponding bond
is interacting with the more highly substituted p-bond (Table 12:
entries 3,4, and 8). This is totally different in the Beller-type
ligand[57]] system Au-BiarylR where the AuI centre is interacting
with the non-substituted p-bond of the biphenyl (Table 12: entry
12). The distance between gold and the phenyl plane of the biaryl
˚
˚
is 3.10 A on average (Au–biaryl plane: 2.955–3.220 A).
The linear geometry of P–Au–Cl in every complex is slightly
distorted, which is seen in the average angle of P–Au–Cl ¼
175.08 (P–Au–Cl: 169.58 (Au-BiarylC) to 176.68 (Au-BiarylO)).
Au-BiarylC has with 169.58 the highest deviation from
the expected 1808 for a linear-coordinated AuI complex
(Table 12: entry 1). This is a result of steric hindrance between
the substituents of the phosphorus atom of the ligand. The
tetramethyl-substituted phenyl ring in BiarylC on one side
repulses the di-tert-butyl moieties on the other side. Therefore
the gold centre is pushed towards the mean plane of the second
phenyl ring and further distorted from the ideal linear geometry.
Another outcome of this effect is the low value for hapticity Z
inAu-BiarylCwithZcalc ¼ 1.13. The average hapticity of the other
mentioned Au-Biaryl complexes is Zcalc/average ¼ 1.70, which
clearly demonstrates the favoured haptacity of Z2-AuI complexes.
Au-BiarylF with Zcalc ¼ 1.91 has the highest calculated hapticity.
Interestingly, the Au-BiarylC complex is the most effective
in our studies in the phenol synthesis of dihydroisocoumarins
(Table 12). We think that the high effectiveness is a result of the
stabilization of AuI in the transition state by the side-on
interaction with the mean plane with the flanking phenyl ring
of the ligand. The fact that different kinds of catalytic systems
either lead to decomposition of the substrate or do not react at all
must be a reliable indicator for reactivity and selectivity.
[54]
˚
length of ,3 A.
The most important data for the Au-Biaryl complexes are
summarized in Table 12. For further clarity and understanding,
the haptacity of the Au centre was calculated using the method
developed by Kochi and coworkers.[55] The measured Au–P
˚
bond length of all complexes varies from 2.22 to 2.25 A, the
˚
Au–Cl bond length from 2.28 to 2.30 A.
The existence of an Au–C interaction to the flanking biaryl
moieties is validated by the measured distance in the solid state
and is therefore is therefore shorter than the sum of the Van der
[56]
˚
Waals radii (3.36 A).
In most cases, Au–Cipso is shorter than the Au–Cortho distance
˚
˚
and ranges from 2.96 A for Au-BiarylC to 3.26 A for Au-
BiarylR (Table 12: entries 1 and 12). For the ligands containing
an amino group in the ortho position of the coordinating second
aryl group, the AuI atom is directed to the Cortho position. The
˚
Au–Cortho distances are 3.17 and 3.12 A, and the Au–N distances
˚
are 3.58 and 3.30 A for Au-BiarylF and Au-BiarylM respec-
tively (Table 12: entries 4 and 8).
If the second phenyl ring of the Buchwald ligand has just one
ortho-substituted position, the AuI centre of Au-BiarylE, F, and M

486
A. S. K. Hashmi et al.
Table 5. More gold(I) biarylphosphine complexes used in this investigation
Cy, cyclohexyl
Entry
Structure
X-ray structure analysis
Me
Me
Me
Me
tBu
tBu
C21
P
P1
Au1
C11
C26
C27
C32
iPr
iPr
Au
1
C28
Cl
iPr
Au-BiarylC
Cy
Cy
P
C31
P1
Au
C36
2
Cl
C38
C38
C38
C37
Au1
Cl1
C42
Au-BiarylD
Cy
P
Cy
C31
Au
P1
3
4
5
C36
Cl
C37
C42
Au1
Cl1
Au-BiarylE
C43
Cy
Cy
P
P1
C31
Me2N
Au
C36
Au1
C37
Cl
N1
C42
Cl1
Au-BiarylF
Cy
P
OMe
Au
Cy
P1
Au1
Cl1
O1
MeO
C31
C36
C37
Cl
C38
O2
C42
Au-BiarylG
Cy
P
Cy
C31
P1
OiPr
O2
C36
C37
O1
iPrO
Au
6
C42
C38
Cl
Au1
Cl1
Au-BiarylH
(Continued)

Coumarins
487
Table 5. (Continued)
Structure
Entry
X-ray structure analysis
Cy
Cy
P1
P
Au1
Cl1
iPr
iPr
Au
Cl
C31
C36
7
C38
C37
C42
iPr
Au-BiarylI
–
Cy
Cy
P
iPr
iPr Au
8
Cl
SO3ꢄNaꢃ
Au-BiarylJ
–
Cy
P
Cy
OMe
MeO
ꢃNaꢄO3S
Au-BiarylK
Au
9
Cl
–
tBu
tBu
P
Au
10
Cl
Au-BiarylL
tBu
tBu
P
P1
C31
Me2N
Au
C36
Au1
C37
11
N1
C42
Cl
Cl1
C38
Au-BiarylM
tBu
tBu
C31
P1
P
C36
iPr
iPr
Au
Cl
C46
C41
12
Au1
Cl1
C42
iPr
Au-BiarylN
(Continued)

488
A. S. K. Hashmi et al.
Table 5. (Continued)
Structure
Entry
X-ray structure analysis
tBu
P
tBu
C22
C21 P1
C32
Au
Cl
C31
13
Au1
Cl1
C40
Au-BiarylO
–
Ph
P
Ph
Me2N
Au
14
Cl
Au-BiarylP
Cy
P
Cy
N
Au
C1
P1
N5
Cl
15
C11
C12
Au1
C16
Cl1
Au-BiarylQ
Cy
Cy
P
N
Au
MeO
C1
Cl
N5
P1
16
017
C16
C11
Au1
Au-BiarylR
Cl1
Table 6. Catalyst development stage 2 screening of biaryl phosphine ligands with two cyclohexyl groups on phosphorus
]
Entry
Ligand
Temperature [8C]
Time [days]
Yield of 7cA
1
2
3
4
5
6
7
8
9
10
Au-BiarylD
Au-BiarylD
Au-BiarylE
Au-BiarylF
Au-BiarylG
Au-BiarylH
Au-BiarylI
Au-BiarylJ
Au-BiarylK
Au-BiarylC
25–50
25
4
5
71 %
67 %
72 %
64 %
58 %
50 %
65 %
–
25–50
25
3
6
25–70
25–70
25–70
25–70
25–70
25
4
6
14
5
7
–
3
75 %
AYield determined by 1H NMR integration.

Coumarins
489
Table 7. Catalyst development stage 3 screening of biaryl phosphine ligands with two tert-butyl groups on phosphorus
]
Bu
5 mol-%
Biaryl Catalyst
Bu
O
O
O
DCM
5 mol-% AgBF4
O
6c
OH
O
7c
Entry
Ligand
Temperature [8C]
Time
Yield of 7cA
1
2
3
4
5
6
7
Au-BiarylB
Au-BiarylL
Au-BiarylL
Au-BiarylM
Au-BiarylN
Au-BiarylO
Au-BiarylO
25–50
25
5 days
5 days
4 days
30 hB
64 %
64 %
63 %
43 %
44 %
66 %
68 %
25–50
25
25–70
25–50
25
10 days
4 days
5 days
AYield by 1H NMR integration.
B decomposition of the substrate after 30 h.
Table 8. Catalyst development stage 4 comparison of different groups on phosphorus for a specific biaryl unit
]
R
P
Au
Cl
5 mol-%
Me2N
R
Bu
Bu
O
O
O
DCM
5 mol-%, AgBF4
O
6c
OH
O
7c
Entry
Ligand
R
T [8C]
Time
Yield of 7cA
1
2
3
Au-BiarylF
Au-BiarylM
Au-BiarylP
Cy
25
6 days
30 hB
64 %
43 %
–
tert-Butyl
25
Phenyl
25–70
5 days
AYield by 1H NMR integration.
BDecomposition of the substrate after 30 h.
Table 9. Catalyst development stage 5 properties of pyrrole-based biaryl units
]
Cy
Cy
P
N
Au
R
Cl
Bu
Bu
O
O
O
DCM
AgBF4, 5 mol-%
O
OH
O
6c
7c
Entry
Ligand
R
Temperature [8C]
Time [h]
Yield of 7cA
1
2
Au-BiarylQ
Au-BiarylR
H
25
25
10
27
14 %
15 %
OMe
AYield by 1H NMR integration.

490
A. S. K. Hashmi et al.
Table 10. Gold-catalyzed synthesis of dihydroisocoumarins 7
R2
R1
R1
5 mol-% Au-Biaryl C
O
O
O
DCM,
5 mol-% AgBF4
R2
O
OH
O
6
7
Entry
Substrate
R1
R2
Product (yield)A
1
2
3
4
5
6
7
6a
6b
6c
6d
6e
6f
Methyl
Propyl
Butyl
H
H
H
H
H
H
7a (48 %)
7b (51 %)
7c (57 %)
7d (40 %)
7e (28 %)
7f (35 %)
–
Phenyl
CH2-OPh
CH2-(2-Methylfuryl)
Phenyl
6g
CH2OH
AYield after workup.
013
C8
C9
C6
07
C5
04
012
C5
01
C10
C9
C3
C1
C1
C5
C11
09
C2
C3
C2
08
C6
C1
01
04
C7
07
02
H1
(a)
(b)
(c)
Fig. 2. Molecular structure of (a) 5e; (b) 6e; and (c) 7e in the solid state.
Table 11. Selected structural data for Au-BiarylS
˚
2.234(2) A
Au1–P1
˚
2.324(3) A
Au1–Cl1
˚
3.1616(5) A
˚
2.227(2) A
˚
2.333(3) A
˚
3.070 A
˚
3.060 A
˚
3.058 A
˚
3.052 A
Au1–Au2
P2
P1
C31
C36
Au2–P2
C71
C76
C77
Au2
Au2–Cl1
Au1
Au1–C37
C78
H1
N1
Au2–C77
H2
N2
C37
Au1–plane1 of the distal ring of the biaryl unit
Au1–plane2 of the distal ring of the biaryl unit
P1–Au1–Cl1
C38
C11
C82
C42
177.14(9)8
135.36(6)8
47.37(7)8
P1–Au1–Au2
Cl1–Au1–Au2
P2–Au2–Cl1
175.56(10)8
135.10(6)8
47.13(7)8
Fig. 3. Structure of Au-BiarylS in the solid state.
P2–Au2–Au1
Cl1–Au2–Au1
Au1–Cl1–Au2
85.49(10)8
Conclusion
We identified a class of biarylphosphinegold(I) complexes that
for the first time allows the cycloisomerization of notoriously
difficult substrates for dihydroisocoumarins. This might be
useful for total synthesis, the western part of ajudazol being just
one potential target.
solution was cooled to 08C. Then nBuLi was added dropwise,
and the solution turned slightly yellow. The solution was
allowed to stir for 2 h at room temperature (RT) before the
oxirane derivative was added dropwise at 08C. Then the mixture
was allowed to warm slowly to RT and stirred for 14 h;
the solution turned orange-reddish. Subsequently, the solution
was hydrolyzed with 20 mL of water. The aqueous phase was
extracted thrice with dichloromethane (DCM) before the com-
bined organic phases were dried over Na2SO4, filtered and
Experimental
General Procedures
General Procedure A: Synthesis of Hydroxyfurans
In a dry Schlenk flask under an inert gas atmosphere, a
solution of 2-methylfuran in dry THF was prepared. The

Coumarins
491
concentrated under vacuum. The residue was purified by flash
column chromatography on silica gel.
(a)
General Procedure B: Synthesis of Alkynylesters
with 1,7-Enyne Substructure
DCC coupling. In a dry Schlenk flask under an inert gas
atmosphere, a solution of hydroxyfuran (from General Proce-
dure A) and propiolic acid in dry DCM was prepared. The
solution was cooled to 08C. A second solution of DCC and
DMAP in DCM was added within 1 h at 08C. The resulting
mixture was stirred for 5 h at RT. A precipitate formed, which
was filtered off and washed with diethyl ether. The resulting
filtrate was washed with brine and the combined organic layers
were dried over Mg2SO4. The solid was removed by filtration
and the solution was concentrated under vacuum. The residue
was purified by flash column chromatography on silica gel.
Mitsunobu Reaction. The alcohol was dissolved in THF
and the solution was cooled to ꢀ108C. The solution was treated
with PPh3 and propiolic acid at that temperature. The resulting
solution was stirred for 10 min at which point diethylazodicar-
boxylatge (DEAD) was added slowly. The mixture was allowed
to slowly warm to room temperature. The conversion was
monitored by TLC and after total consumption of the starting
material, the solvent was removed under vacuum. The crude
product was directly purified by column chromatography.
(b)
General Procedure C: Gold-catalyzed
Cycloisomerization of 1,7-Enynes
The enyne derivative was dissolved in [D2]DCM and an
NMR spectrum was taken as a reference. Then 5 mol-% of the
catalyst and 5 mol-% of silver salt were added. The reaction
progress was monitored by 1H NMR spectroscopy. Then the
Fig. 4. Fit of superimposed Au-biaryl complexes analysed by X-ray
crystal structure determination. Linear subunit: top ¼ phosphorous;
middle ¼ gold; bottom ¼ chlorine.
Table 12. Selected crystallographic data and haptacity from Kochi et al.[55]
˚
Au–P [A]
˚
Au–Cl [A]
˚
Au–Cortho [A]
˚
Au–Cipso [A]
˚
Au–plane [A]
Entry
Angle P–Au–Cl [8]
Hapticity Zcalc
1 Au-BiarylC
2.241
2.228
2.233
2.231
2.235
2.224
2.228
2.238
2.239
2.246
2.233
2.232
2.291
2.283
2.288
2.286
2.297
2.281
2.283
2.294
2.285
2.289
2.289
2.287
169.48
3.171
3.354
3.317
3.538
3.266A
3.699
3.167A
3.641
3.253
3.605
3.195
3.583
3.206
3.474
3.116A
3.546
3.229
3.732
3.227
3.358
3.345
3.544
3.674
3.333B
2.956
3.160
3.194
3.193
3.193
3.113
3.121
3.266
3.135
3.052
3.215
3.259
2.955
3.140
3.132
3.104
3.145
3.060
3.076
3.091
3.046
3.037
3.188
3.220
1.13
2 Au-BiarylD
3 Au-BiarylE
4 Au-BiarylF
5 Au-BiarylG
6 Au-BiarylH
7 Au-BiarylI
8 Au-BiarylM
9 Au-BiarylN
10 Au-BiarylO
11 Au-BiarylQ
12 Au- BiarylR
175.45
175.49
175.38
173.42
176.33
176.36
172.94
176.19
176.64
176.37
175.38
1.50C
1.81C
1.91
1.81
1.77
1.74C
1.54
1.82
1.43
1.58
1.74
ADistance to the ortho-substituted biphenyl.
BDistance to the unsubstituted ortho position of the biphenyl.
CIn good agreement with the experimental data described in the literature.[50,58]

492
A. S. K. Hashmi et al.
solvent was evaporated and the resulting residue was purified by
flash column chromatography on silica gel.
(23 %) [Mþ], 151 (12), 113 (9), 96 (100), 95 (58), 81 (14); m/z
(HR-MS, 70eV) 182.1334; calc. for C11H18O2: 182.1307.
General Procedure D: Preparation of AuI Complexes
with Phosphine Ligands
2-(5-Methylfuran-2-yl)-1-phenylethanol (5d)
According to General Procedure A, 2-methylfuran (3.97 mL,
44.0 mmol) was treated with nBuli in hexanes (17.6 mL, 2.5 M,
44.0 mmol) and 1,2-epoxystyrene (5.02 mL, 44.0 mmol) in
25 mL THF. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 15 : 1 : 2)
to give 5d (3.73 g, 18.5 mmol, 42 %) as a slightly yellow oil. R
(light petroleum/ethyl acetate/DCM, 15 : 1 : 2) 0.10. nmax (film)/
cmꢀ1 3418, 3066, 3033, 2920, 1709, 1609, 1568, 1494, 1452,
1218, 1051, 1024, 784 cm. dH (CDCl3, 500 MHz) 2.27 (s, 4H),
2.97 (m, 2H), 4.95 (dd, J 8.5 and 3.9, 1H), 5.88 (d, J 2.8, 1H),
Tetrahydrothiophengold(I) chloride (1 equiv.) was dissolved
in dichloromethane and the phosphine ligand (1 equiv.) was
slowly added (,45 min) to this solution with stirring. After
60 min, the solid was filtered off, washed with dichloromethane
and dried under vacuum.
Single Crystals for X-Ray Crystal Structure Analyses
All single crystals were grown by slow evaporation of the
solvent.
3
5.96 (d, J 2.9, 1H), 7.28 (t, JH,H 6.8, 1H), 7.36 (m, 4H). dC
(CDCl3, 125 MHz) 13.5 (q), 38.5 (t), 72.8 (d), 106.1 (d), 108.1
(d), 125.7 (d), 127.6 (d), 128.3 (d), 143.4 (s), 150.4 (s), 151.2 (s).
m/z (EI) 202 (5 %) [Mþ], 107 (24), 96 (100), 95 (55), 79 (20), 77
(12); m/z (HR-MS, 70eV) 202.0994; calc. for C13H14O2:
202.0975. Anal. calc. for C13H14O2 (202.1): C 77.20, H 6.98.
Found: C 77.14, H 6.85 %.
Syntheses
1-(5-Methylfuran-2-yl)propan-2-ol (5a)
According to General Procedure A, 2-methylfuran (4.51 mL,
50.0 mmol) was treated with nBuLi in hexanes (20.0 mL, 2.5 M,
50.0 mmol) and 1,2-epoxypropane (2.13 mL, 50.0 mmol) in
20 mL THF. The crude product was purified by silica gel flash
chromatography (hexane/methyltertbutylehter (MTBE) 5 : 1) to
give 5a (4.70 g, 33.5 mmol, 67 %) as a colourless oil. Rf
(hexanes/MTBE, 5 : 1) 0.14. dH (CDCl, 300 MHz) 1.20 (d,
J 6.2, 3H), 1.92 (s, 1H), 2.23 (s, 3H), 2.67 (dq, J 7.6, 4.5, 2H),
3.97–4.05 (m, 1H), 5.84 (d, J 2.9, 1H), 5.94 (d, J 3.0, 1H). dC
(CDCl, 75 MHz) 13.5 (s), 22.6 (s), 37.9 (d), 66.7 (t), 106.0 (t),
107.7 (t), 150.9 (q), 151.1 (q).
1-(5-Methylfuran-2-yl)-3-phenoxypropan-2-ol (5e)
According to General Procedure A, 2-methylfuran (3.97 mL,
44.0 mmol) was treated with nBuli in hexanes (17.6 mL, 2.5 M,
44.0 mmol) and 1,2-epoxy-3-phenoxypropane (8.94 mL,
66.0 mmol) in 35 mL THF. The crude product was purified by
recrystallization in hexane to give 5e (4.31 g, 18.5 mmol, 42 %)
as a white solid. Mp 70–718C. nmax (KBr)/cmꢀ1 3449, 3066,
2832, 1602, 1499, 1252, 1043. dH (CDCl3, 300 MHz) 2.24 (s,
3H), 2.39 (d, 3JH,H 4.3, 1H), 2.91 (d,3JH,H 6.5, 2H), 3.91 (dd, J
9.4, J 6.5, 1H), 3.99 (dd, J 9.4, 4.0, 1H), 4.27 (m, J 4.1, 2.4, 1H),
5.86 (d, J 2.9, 1H), 6.00 (d, J 3.0, 1H), 6.89 (m, 1H), 6.91 (m,
1H), 6.95 (tt, J 7.3, 1.0, 1H), 7.26 (d, J 7.5, 1H), 7.28 (d, J 7.5,
1H). dC (CDCl, 75 MHz) 13.6 (q), 32.5 (t), 69.1 (t), 71.1 (d),
106.2 (d), 108.1 (d), 114.6 (d), 121.2 (d), 129.5 (d), 149.8 (s),
151.3 (s), 158.6 (s). m/z (EI) 232 (58 %) [Mþ], 162 (5), 160 (7),
121 (42), 119 (8), 113 (6), 96 (38), 95 (100), 94 (6), 91 (5);
m/z (HR-MS, 70eV) 232.1082; calc. for C14H16O3: 232.1099.
Anal. calc. for C14H16O3 (232.1): C 72.39, H 6.94. Found:
C 72.16, H 6.93 %.
1-(5-Methylfuran-2-yl)pentan-2-ol (5b)
According to General Procedure A, 2-methylfuran
(4.51 mL, 50.0 mmol) was treated with nBuLi in hexanes
(20.0 mL, 2.5 M, 50.0 mmol) and 1,2-epoxypentane (5.19 mL,
50.0 mmol) in 20 mL THF. The crude product was purified by
silica gel flash chromatography (hexane/MTBE 5 : 1) to give
5b (2.86 g, 17.0 mmol, 34 %) as a slightly yellow oil.
R (hexanes/ MTBE 5 : 1) 0.19. nmax (film)/cmꢀ1 3384, 2959,
2927, 2873, 1570, 1454, 1219, 1123, 1021, 782. dH (CDCl3,
3
300 MHz) 0.91 (t, JH,H 7.0, 3H), 1.44 (m, 4H), 1.98 (s, 1H),
3
2
2.22 (s, 3H), 2.68 (qd, JH,H 8.0 and JH,H 4.1, 2H), 3.83 (m,
1H), 5.83 (d, 3JH,H 2.9, 1H), 5.94 (d, 3JH,H 3.0, 1H). dC (CDCl3,
75 MHz) 13.4 (q), 14.0 (q), 18.8 (t), 36.2 (t), 38.8 (t), 70.1 (d),
106.0 (d), 107.6 (d), 151.0 (s), 151.0 (s). m/z (electrospray
ionization (EI)) 168 (24 %) [Mþ], 151 (11), 96 (100), 95 (69),
81 (17); m/z (high-resolution (HR)-MS, 70eV) 168.1166; calc.
for C10H16O2: 168.1150.
1,3-Bis(5-methylfuran-2-yl)propan-2-ol (5f)
(a) 2-Methyl-5-(oxiran-2-ylmethyl)furan. According to
General Procedure A, 2-methylfuran (3.08 mL, 37.5 mmol)
was treated with nBuLi in hexanes (15.0 mL, 2.5 M, 37.5 mmol)
and 2-(chloromethyl)oxirane (4.40 mL, 56.3 mmol) in 30 mL
THF. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 15 : 1 : 2)
to give 2-methyl-5-(oxiran-2-ylmethyl)furan 5f (2.68 g,
19.4 mmol, 41 %) as a colourless oil. R (light petroleum/ethyl
acetate (EE)/DCM 15 : 1 : 2) 0.13. nmax (KBr)/cmꢀ1 3418, 2954,
2923, 1757, 1715, 1569, 1430, 1216. dH (CDCl3, 300 MHz) 5.97
(d, J 3.0, 1H), 5.84 (m, 1H), 3.13 (m, 1H), 2.89 (dd, J 15.5, 5.5,
1H), 2.72 (m, 2H), 2.52 (dd, J 5.0, 2.6, 2H), 2.23 (s, 3H). dC
(CDCl, 75 MHz) 151.0 (q), 149.2 (q), 107.2 (t), 106.0 (t), 50.46
(t), 46.7 (d), 31.5 (d), 13.4 (s). m/z (EI) 138 (40 %) [Mþ], 95
(100), 43 (14); m/z (HR-MS, 70eV) 138.0680; calc. for
C8H10O2: 138.0681.
1-(5-Methylfuran-2-yl)hexan-2-ol (5c)
According to General Procedure A, 2-methylfuran (3.97 mL,
44.0 mmol) was treated with nBuli in hexanes (17.6 mL, 2.5 M,
44.0 mmol) and 1,2-epoxyhexane (5.30 mL, 44.0 mmol) in
20 mL THF. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 20 : 1 : 2)
to give 5c (3.61 g, 19.8 mmol, 45 %) as a slightly yellow oil. R
(light petroleum/ethyl acetate/DCM, 20 : 1 : 2) 0.20. nmax (film)/
cmꢀ1 3484, 2965, 2932, 2872, 1759, 1706, 1431, 1381, 1242,
3
1169, 1096 cm. dH (CDCl3, 500 MHz) 0.88 (t, JH,H 7.1, 3H),
1.31–1.49 (m, 6H), 1.86 (s, 1H), 2.23 (s, 3H), 2.69 (dq, 3JH,H 8.0,
4.1, 2H), 3.82 (m, 1H), 5.85 (s, 1H), 5.95 (d, 3JH,H 3.0, 1H). dC
(CDCl3, 125 MHz) 13.5 (q), 14.0 (q), 22.7 (t), 27.8 (t), 36.3 (t),
70.4 (d), 106.0 (d), 107.7 (d), 151.0 (s), 151.1 (s). m/z (EI) 182
(b) 5f. According to General Procedure A, 2-methylfuran
(164mg, 2.00mmol) was treated with nBuLi in hexanes (800mL,
2.5 M, 2.00 mmol) and 2-methyl-5-(oxiran-2-ylmethyl)furan

Coumarins
493
(276 mg, 2.00 mmol) in 10 mL THF. The crude product was
purified by silica gel flash chromatography (light petroleum/
ethyl acetate/DCM 20 : 1 : 2) to give 5f (189 mg, 0.86 mmol,
43 %). R (light petroleum/ethyl acetate/DCM, 20 : 1 : 2) 0.13.
nmax (film)/cmꢀ1 3418, 2922, 1710, 1570, 1431, 1384, 1218,
1177, 1046, 1023, 996, 962, 935, 784. dH (CDCl3, 300 MHz)
2.21 (bs, 1H), 2.24 (s, 6H), 2.76 (m, 4H), 4.12 (m, 1H), 5.86 (dd,
J 2.9, 1.0, 2H), 5.98 (d, J 2.9, 2H). dC (CDCl3, 75 MHz) 13.5
(q, 2C), 35.4 (t, 2C), 69.3 (d, 2C), 106.1 (d, 2C), 107.9 (d, 2C),
150.5 (s, 2C), 151.1 (s, 2C). m/z (EI) 220 (89 %) [Mþ], 202 (7),
161 (9), 151 (9), 125 (19), 124 (33), 97 (16), 96 (76), 95 (100), 83
(20), 81 (14); m/z (HR-MS, 70eV) 220.1068; calc. for C13H16O3:
220.1099. Anal. calc. for C13H16O3 (220.3): C 70.89, H 7.32.
Found: C 70.22, H 7.36 %.
1-(5-Methylfuran-2-yl)pentan-2-yl Propiolate (6b)
According to General Procedure B, 5b (1.68 g, 10.0 mmol)
was treated with propiolic acid (616 mL, 10.0 mmol), DCC
(2.06 g, 10.0 mmol), and DMAP (31.0 mg, 250 mmol) in 15 mL
DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate 20 : 1) to give
6b (550 mg, 2.50 mmol, 25 %) as a colourless oil. R (light
petroleum/ethyl acetate, 20 : 1) 0.27. nmax (film)/cmꢀ1 3267,
2962, 2936, 2876, 2118, 1713, 1383, 1361, 1233, 1022, 786,
756. dH (CDCl3, 300 MHz) 0.89 (t, 3JH,H 7.3, 3H), 1.37 (m, 2H),
1.58 (m, 2H), 2.22 (s, 3H), 2.84 (d, J 6.2, 2H), 2.84 (s, 1H), 5.17
(m, 1H), 5.82 (d, 3JH,H 2.8, 1H), 5.92 (d, J 2.9, 1H). dC (CDCl3,
75 MHz) 13.6 (q), 13.9 (q), 18.6 (t), 32.9 (t), 35.7 (t), 74.6 (d),
75.3 (d), 75.5 (s), 106.2 (d), 108.1 (d), 149.2 (s), 151.3 (s), 152.4
(s). m/z (EI) 220 (5 %) [Mþ], 150 (68), 121 (72), 95 (100); m/z
(HR-MS, 70eV) 220.1089; calc. for C13H16O3: 220.1099.
(2S,3S)-3-(5-Methylfuran-2-yl)-3-phenylpropane-
1,2-diol (5g)
1-(5-Methylfuran-2-yl)hexan-2-yl Propiolate (6c)
In an oven-dried Schlenk flask under an inert gas atmo-
sphere, a solution of 2-methylfuran (3.97 mL, 44.0 mmol) in dry
THF (30.0 mL) was prepared. The solution was cooled to 08C.
Then nBuLi in hexanes (2.5 M, 17.6 mL, 44.0 mmol) was added
dropwise and the solution turned slightly yellow. Afterwards the
solution was stirred for 2 h at RT before ((2R,3R)-3-phenyl-
oxiran-2-yl)methanol (7.56 mL, 33.0 mmol) was added drop-
wise at 08C. Then the mixture was allowed to warm slowly to RT
and stirred for 14 h and the solution turned orange-reddish.
Subsequently the solution was hydrolyzed with water (20 mL).
The aqueous phase was extracted with DCM (15 mL) before the
combined organic phases were dried over Na2SO4, filtered, and
concentrated under vacuum. Purification of the product by
column chromatography (SiO2, light petroleum/ethyl acetate/
DCM 3 : 1 : 2) provided 5 g (700 mg, 3.01 mmol) as a slightly
yellow oil in 9 % yield (only one diastereoisomer observed). Rf
(light petroleum/EE/DCM 3 : 1 : 2) 0.08. nmax (film)/cmꢀ1 3420,
2949, 2910, 1616, 1566, 1496, 1453, 1220, 1025, 779, 747, 708,
615. dH (CDCl3, 300 MHz) 2.23 (s, 3H), 2.80 (s, 2H), 3.42
(dd, J 11.5, 6.7, 1H), 3.59 (dd, J 11.5, 2.9, 1H), 3.97 (d, J 8.8,
1H), 4.23 (m, 1H), 5.84 (d, J 2.9, 1H), 5.97 (d, J 3.0, 1H), 7.28
(m, 5H). dC (CDCl3, 75 MHz) 13.5 (q), 48.5 (d), 64.7 (t), 73.6
(d), 106.0 (d), 107.5 (d), 127.0 (d, 2C), 128.5 (d, 2C), 128.8 (d),
139.1 (d), 151.1 (s), 152.3 (s). m/z (EI) 232 (5 %) [Mþ], 201 (4),
173 (4), 172 (38), 171 (100), 163 (5), 162 (7), 151 (9), 128 (6),
113 (6), 107 (6), 105 (5), 91 (7), 77 (4); m/z (HR-MS, 70eV)
232.1114; calc. for C14H16O3: 232.1099.
According to General Procedure B, 5c (729 g, 4.0 mmol) was
treated with propiolic acid (246 mL, 4.00 mmol), DCC (825 mg,
4.00 mmol), and DMAP (12.0 mg, 100 mmol) in 15 mL DCM.
The crude product was purified by silica gel flash chromatogra-
phy (light petroleum/ethyl acetate 30 : 1) to give 6c (281 mg,
1.20 mmol, 30 %) as a yellow oil. R (light petroleum/ethyl
acetate, 30 : 1) 0.14. nmax (film)/cmꢀ1 3281, 2959, 2933, 2863,
2117, 1714, 1570, 1235, 1022, 785, 735. dH (CDCl3, 500 MHz)
0.87 (t, 3JH,H 7.0, 3H), 1.29 (m, 4H), 1.60 (m, 2H), 2.22 (s, 3H),
2.84 (m, 3H), 5.16 (quin, 3JH,H 6.3, 1H), 5.83 (d, 3JH,H 2.7, 1H),
5.93 (d, J 2.9, 1H). dC (CDCl3, 75 MHz) 13.5 (q), 14.0 (q), 22.7
(t), 33.0 (t), 33.4 (t), 74.6 (d), 75.1 (s), 75.7 (d),106.3 (d), 108.2
(d), 147.6 (s), 149.6 (s), 152.5 (s). m/z (EI) 234 (7 %) [Mþ], 216
(5), 213 (8), 212 (5), 201 (9), 165 (14), 164 (96), 161 (13), 151
(20), 121 (75), 113 (13), 108 (11), 96 (9), 95 (100), 92 (18), 91
(25); m/z (HR-MS, 70eV) 234.1290; calc. for C14H18O3:
234.1256.
2-(5-Methylfuran-2-yl)-1-phenylethyl propiolate (6d)
According to General Procedure B, 5d (809 mg, 4.00 mmol)
was treated with propiolic acid (246 mL, 4.00 mmol), DCC
(825 mg, 4.00 mmol), and DMAP (12 mg, 100 mmol) in 15 mL
DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate 10 : 1) to give
6d (295 mg, 1.16 mmol, 29 %) as a colourless oil. R (light
petroleum/ethyl acetate, 10 : 1) 0.35. nmax (film)/cmꢀ1 3278,
2920, 2119, 1721, 1230, 1026, 754, 701. dH (CD2Cl2, 300 MHz)
2.23 (s, 3H), 2.97 (s, 1H), 3.09 (dd, J 5.8, 1H), 3.24 (dd, J 8.1,
1H), 5.85 (m, 1H), 5.89 (d, J 7, 1H), 6.06 (m, 1H), 7.35 (m, 5H).
dC (CD2Cl2, 75 MHz) 13.5 (q), 35.3 (t), 74.8 (s), 75.1 (d), 76.9
(d), 106.4 (d), 108.5 (d), 126.9 (d), 128.8 (d), 128.8 (s), 139.1 (d),
148.9 (s), 151.7 (s), ester carbon not detected. m/z (EI) 254 (3 %)
[Mþ], 185 (11), 184 (45), 159 (40), 96 (7), 95 (100); m/z (HR-
MS, 70eV) 254.0970; calc. for C16H14O3: 254.0943.
1-Methyl-2-(5-methylfuran-2-yl)ethylprop-2-ynoate (6a)
According to General Procedure B, 5a (2.00 g, 14.0 mmol)
was treated with propiolic acid (879 mL, 14.0 mmol), DCC
(2.94 g, 14.0 mmol), and DMAP (18 mg, 140 mmol) in 50 mL
DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 10 : 1 : 2)
to give 6a (1.05 g, 5.46 mmol, 39 %) as a colourless oil. R (light
petroleum/ethyl acetate/DCM, 10 : 1 : 2) 0.47. nmax (film)/cmꢀ1
3276, 2925, 2118, 1799, 1570, 1452, 1384, 1235, 1190, 1134,
1049, 1021, 786, 757. dH (CDCl3, 300 MHz) 1.26 (d, 3JH,H 6.3,
3H), 2.19 (s, 3H), 2.84 (dq, J 6.5, 2H), 2.86 (s, 1H), 5.18 (sext,
3JH,H 6.4, 1H), 5.80 (dd, J 2.9, 1.0, 1H), 5.92 (d, J 3.0, 1H). dC
(CDCl, 75 MHz) 13.3 (q), 19.2 (q), 34.2 (t), 71.9 (d), 74.4 (d),
74.8 (s), 106.0 (d), 107.9 (d), 148.8 (s), 151.0 (s), 151.9 (s). m/z
(EI) 192 (6 %) [Mþ], 163 (6), 162 (8), 151 (10), 123 (14), 122
(95), 121 (6), 107 (8), 96 (7), 95 (100), 91 (5); m/z (HR-MS,
70eV) 192.0795; calc. for C11H12O3: 192.0786.
2-(5-Methylfuran-2-yl)-1-(phenoxymethyl)ethyl
Prop-2-ynoate (6e)
According to General Procedure B, 5e (1.64 g, 7.00 mmol)
was treated with propiolic acid (430 mL, 7.00 mmol), DCC
(1.45 g, 7.00 mmol), and DMAP (9.0 mg, 70 mmol) in 48 mL
DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate 25 : 1) to give
6e (497 mg, 1.75 mmol, 25 %) as a colourless oil. R (light
petroleum/ethyl acetate, 25 : 1) 0.13. nmax (film)/cmꢀ1 3272,

494
A. S. K. Hashmi et al.
2924, 2119, 1717, 1548, 1496, 1228, 1044, 754, 692. dH (CDCl3,
300 MHz) 2.28 (s, 3H), 2.97 (s, 1H), 3.12 (m, J 15.2, 6.5, 2H),
4.12 (m, J 10.5, 3.5, 2H), 5.56 (m, 1H), 5.91 (d, J 3.0, 1H), 6.05
(d, J 3.0, 1H), 6.93 (d, J 8.8, 2H), 7.01 (t, J 7.4, 1H), 7.32 (m, J
8.7, 2H). dC (CDCl3, 75 MHz) 13.2 (q), 29.2 (t), 67.4 (t), 72.7
(d), 74.3 (s), 75.5 (d), 106.1 (d), 108.3 (d), 114.4 (d, 2C), 121.1
(d), 129.3 (d, 2C), 147.8 (s), 151.2 (s), 151.7 (s), 158.1 (s). m/z
(EI) 284 (4 %) [Mþ], 151 (4), 122 (9), 121 (100), 95 (33), 77 (7);
m/z (HR-MS, 70eV) 284.1041; calc. for C17H16O4: 284.1049.
Anal. calc. for C17H16O4 (284.3): C 71.82, H 5.67. Found: C
71.71, H 5.74 %.
6-tetramethylbiphenyl-2-yl)phospinegold(I) chloride (15 mg,
21 mmol) and silver tetrafluoroborate (4.0 mg, 21 mmol) in
1 mL [D2]DCM. The crude product was purified by silica gel
flash chromatography (light petroleum/ethyl acetate/DCM
15 : 1 : 1) to give 7g (39.0 mg, 205 mmol, 48 %) as a white solid.
Mp 75–768C. R (light petroleum/ethyl acetate/DCM, 15 : 1 : 1)
0.45. dH (CDCl3, 300 MHz) 1.50 (d, 3JH,H 6.3, 3H), 2.22 (s, 3H),
2.87 (d, 3JH,H 7.2, 2H), 4.69 (sext, 3JH,H 6.4 and 7.2, 1H), 6.57
(d, JH,H 7.5, 1H), 7.25 (d, JH,H 7.4, 1H), 11.24 (s, 1H). dC
(CDCl3, 75 MHz) 15.4 (q), 20.7 (q), 34.5 (t), 76.3 (d), 107.5 (s),
117.1 (d), 125.3 (s), 136.5 (s), 136.8 (d), 160.5 (s), 170.4 (s). m/z
(EI) 192 (100 %) [Mþ], 174 (35), 173 (7), 163 (18), 162 (8), 159
(21), 151 (12), 149 (8), 148 (33), 146 (9), 145 (7), 131 (9), 120
(11), 119 (5), 113 (8), 92 (12), 91 (27), 77 (6); m/z (HR-MS,
70eV) 192.0788; calc. for C11H12O3: 192.0786.
3
3
2-(5-Methylfuran-2-yl)-1-[(5-methylfuran-2-yl)methyl]
ethyl Prop-2-ynoate (6f)
According to General Procedure B, 5f (1.00 g, 4.54 mmol)
was treated with propiolic acid (280 mL, 4.54 mmol), DCC
(938 g, 4.54 mmol), and DMAP (6 mg, 45 mmol) in 25 mL
DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 15 : 1 : 1)
to give 6f (210 mg, 772 mmol, 17 %) as a colourless oil. R (light
petroleum/ethyl acetate/DCM, 15 : 1 : 1) 0.67. nmax (film)/cmꢀ1
3271, 2923, 2118, 1716, 1616, 1569, 1234, 1190, 1023, 995,
786, 751. dH (CDCl3, 300 MHz) 2.23 (s, 6H), 2.83 (s, 1H), 2.85–
2.96 (m, 4H), 5.36 (q, J 6.3, 1H), 5.83 (m, 2H), 5.97 (d, J 3.0,
2H). dC (CDCl3, 75 MHz) 13.5 (q), 32.1 (t), 70.9 (s), 73.5 (d),
74.6 (d), 106.1 (d), 108.3 (d), 148.6 (s), 151.3 (s), 151.9 (s). m/z
(EI) 272 (17 %) [Mþ], 218 (8), 203 (11), 202 (76), 187 (7), 162
(7), 160 (10), 159 (57), 151 (8), 145 (6), 121 (30), 113 (6), 96 (7),
95 (100), 91 (6); m/z (HR-MS, 70eV) 272.1049; calc. for
C16H16O4: 272.1049. Anal. calc. for C16H16O4 (272.3): C
70.57, H 5.92. Found: C 70.77, H 5.98 %.
8-Hydroxy-7-methyl-3-propylisochroman-1-one (7b)
According to General Procedure C, 6b (35.0 mg, 159 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,6-
tetramethylbiphenyl-2-yl)phospinegold(I) chloride (6 mg,
8 mmol) and silver tetrafluoroborate (2 mg, 8 mmol) in 1 mL
[D2]DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate 15 : 1) to give 7b
(18 mg, 37 mmol, 53 %) as a white solid. Mp 768C. R (light
petroleum/ethyl acetate, 15 : 1) 0.33. nmax (film)/cmꢀ1 3438,
3059, 2946, 2929, 1664, 1623, 1463, 1429, 1377, 1253, 1175,
1150, 1131, 807, 763. dH (CDCl3, 500 MHz) 0.96 (t, 3JH,H 7.3,
3H), 1.44–1.61 (m, 3H), 1.85 (m, 1H), 2.22 (s, 3H), 2.87 (m, 2H),
3
3
4.54 (m, 1H), 6.57 (d, JH,H 7.4, 1H), 7.24 (d, JH,H 7.4, 1H),
11.24 (s, 1H). dC (CDCl3, 125 MHz) 13.8 (q), 15.4 (q), 18.1 (t),
32.8 (t), 36.8 (t), 79.7 (d), 107.7 (s), 117.1 (d), 125.2 (s), 136.7
(s), 136.7 (d), 160.5 (s), 170.4 (s). m/z (EI) 221 (14 %) [(M þ
H)þ], 220 (100) [Mþ], 202 (35), 187 (10), 184 (15), 177 (9), 173
(22), 165 (9), 164 (7), 163 (8), 161 (23), 160 (11), 149 (19), 148
(27), 120 (7), 91 (13); m/z (HR-MS, 70eV) 220.1082; calc. for
C13H16O3: 220.1099. Anal. calc. for C13H16O3 (220.3): C 70.89,
H 7.32. Found: C 70.20, H 7.22 %.
(2S,3S)-3-(5-Methylfuran-2-yl)-3-phenylpropane-1,2-
diyl Dipropiolate (6g)
In an oven-dried Schlenk flask under an inert gas atmo-
sphere, a solution of 5g (480 mg, 2.07 mmol) and propiolic acid
(250 mL, 4.11 mmol) in dry DCM (15 mL) was prepared. The
solution was cooled to 08C. A solution of DCC (500 mg,
2.43 mmol) and DMAP (5.0 mg, 41 mmol) in DCM (5 mL) was
added within 1 h at 08C. The resulting mixture was stirred for 5 h
at RT. Then the obtained precipitate was filtered off and washed
with diethyl ether. The resulting filtrate was washed with brine
and the combined organic layers dried over Mg2SO4. The solid
was removed by filtration and the solution was concentrated
under vacuum. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 15 : 1 : 2)
to provide 6g (100 mg, 0.30 mmol, 15 %) as a colourless oil. Rf
(light petroleum/EE/DCM 15 : 1 : 2) 0.11. nmax (film)/cmꢀ1
3536, 3484, 3429, 3410, 3284, 3266, 2123, 1719, 1243, 1207,
1166, 1060, 755, 744, 701. dH (CDCl3, 300 MHz) 2.24 (s, 3H),
2.81 (s, 1H), 2.91 (s, 1H), 4.19 (dd, J 12.2, 6.3, 1H), 4.29 (d, J
9.2, 1H), 4.38 (dd, J 12.2, 2.9, 1H), 5.85 (m, J 3.0, 2H), 6.03 (d, J
3.1, 1H), 7.30 (m, 5H). dC (CDCl3, 75 MHz) 13.5 (q), 46.2 (d),
65.2 (t), 73.7 (s), 73.9 (s), 74.1 (s), 75.7 (d, 2C), 106. 3 (d), 108.7
(d), 127.5 (d), 128.5 (d, 2C), 128.6 (d, 2C), 137.2 (s), 149.9 (s),
151.5 (s), 152.1 (s), 152.1 (s). m/z (EI) 336 (3 %) [Mþ], 266 (26),
237 (8), 221 (7), 208 (9), 179 (11), 172 (45), 171 (100), 161 (7),
151 (9), 141 (612), 128 (15), 125 (15), 115 (11), 91 (9); m/z (HR-
MS, 70eV) 336.1010; calc. for C20H16O5: 336.0998.
3-Butyl-8-hydroxy-7-methyl-isochroman-1-one (7c)
According to General Procedure C, 6c (35 mg, 149 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,6-
tetramethylbiphenyl-2-yl)phospinegold(I) chloride (5 mg,
7 mmol) and silver tetrafluoroborate (1 mg, 7 mmol) in 1 mL
[D2]DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate 10 : 1) to give 7c
(20 mg, 85 mmol, 57 %) as a white solid. Mp 528C. R (light
petroleum/DCM, 10 : 1) 0.23. nmax (film)/cmꢀ1 3450, 2953,
2934, 2859, 1665, 1457, 1438, 1255, 1174, 1147, 1127, 806,
3
729. dH (CDCl3, 500 MHz) 0.91 (t, JH,H 7.2, 3H), 1.32–1.47
(m, 3H), 1.47–1.52 (m, 1H), 1.65–1.74 (m, 1H), 1.81–1.91
(m, 1H), 2.22 (s, 3H), 2.87 (m, 2H), 4.52 (m, 1H), 6.57
3
3
(d, JH,H 7.4, 1H), 7.24 (d, JH,H 7.4, 1H), 11.24 (s, 1H). dC
(CDCl3, 125 MHz) 13.9 (q), 15.4 (q), 22.4 (t), 27.0 (t), 32.8 (t),
34.5 (t), 80.0 (d), 107.7 (s), 117.1 (d), 125.2 (s), 136.7 (q), 136.7
(d), 160.5 (q), 170.4 (q). m/z (EI) 234 (100 %) [Mþ], 216 (22),
201 (9), 177 (10), 174 (13), 173 (11), 165 (9), 164 (7), 163 (6),
162 (14), 161 (30), 160 (8), 149 (17), 148 (25), 120 (6), 119 (5),
91 (11); m/z (HR-MS, 70eV) 234.1250; calc. for C14H18O3:
234.1256. Found: C 71.77, H 7.74. Found: C 71.23, H 7.54 %.
8-Hydroxy-3,7-dimethylisochroman-1-one (7a)
8-Hydroxy-7-methyl-3-phenylisochroman-1-one (7d)
According to General Procedure C, 6g (82.0 mg, 427 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,
According to General Procedure C, 6d (35 mg, 140 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,

Coumarins
495
6-tetramethylbiphenyl-2-yl)phospinegold(I) chloride (5 mg,
7 mmol) and silver tetrafluoroborate (1 mg, 7 mmol) in 1 mL
[D2]DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 25 : 1 : 4)
to give 7d (14 mg, 56 mmol, 40 %) as a white solid. R (light
petroleum/ethyl acetate/DCM, 25 : 1 : 4) 0.38. nmax (film)/cmꢀ1
3443, 2940, 1676, 1616, 1458, 1420, 1226, 1128, 802, 777, 705.
Synthesis of (tetrahydrothiophene)AuCl
HAuCl4 ꢁ 2H2O (1.13 g, 3 mmol) was dissolved in H2O/
EtOH (15 mL, 4 : 1) and tetrahydrothiophene (tht) (790 mg,
9 mmol) was added dropwise. The yellow solution became
colourless and (tht)AuCl precipitated. It was filtered and dried
under high vacuum. (tht)AuCl (780 mg, 2.43 mmol, 81 %) was
obtained as a white powder. dH (250 MHz, CDCl3) 2.16–2.27
(m, 4H), 3.39–3.49 (m, 4H)
d
H (CDCl3, 500 MHz) 2.25 (s, 3H), 3.08 (dd, J 16.4 and J 3.2,
1H), 3.27 (dd, J 16.3, 4.1, 1H), 5.56 (dd, J 12.2, 3.2, 1H), 6.63 (d,
3JH,H 7.4, 1H), 7.29 (d, 3JH,H 7.4, 1H), 7.34–7.46 (m, 5H), 11.21
(s, 1H). dC (CDCl3, 125 MHz) 15.5 (q), 35.1 (t), 81.0 (d), 117.1
(d), 125.5 (s), 126.1 (d, 2C), 128.7 (d, 2C), 128.8 (d, 2C), 136.4
(s), 137.0 (d), 138.1 (s), 160.6 (s), 170.2 (s). m/z (EI) 254 (79 %)
[Mþ], 237 (17), 236 (100), 235 (13), 208 (28), 207 (9), 180 (5),
179 (13), 178 (10), 165 (17), 163 (7), 162 (8), 151 (13), 148 (9),
113 (9), 91 (7); m/z (HR-MS, 70eV) 254.0922; calc. for
C16H14O3: 254.0922.
Triphenylphosphinegold(I) p-Tolylsulfonate
(Au-PhosphineA)
A mixture of (triphenylphosphine)gold(I) chloride (40 mg,
0.15 mmol) and silver(I) tosylate (AgOTs) (43 mg, 0.15 mmol)
was suspended in DCM. The reaction mixture was stirred at
room temperature for 1 h, the solvent was evaporated, and the
crude product was dissolved in DCM. The mixture was then
filtered through a pad of Celite, and the solvent evaporated under
reduced pressure to give Au-PhosphineA as a white solid. Yield
98 %. dH (CDCl3, 500 MHz) 2.34 (s, 3H), 7.11–7.82 (m, 19H).
dP (CDCl3, 202 MHz) 30.34.
8-Hydroxy-7-methyl-3-(phenoxymethyl)isochroman-
1-one (7e)
According to General Procedure C, 6e (225 mg, 791 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,6-
tetramethylbiphenyl-2-yl)phospinegold(I) chloride (28 mg,
40 mmol) and silver tetrafluoroborate (8 mg, 40 mmol) in
10 mL DCM. The crude product was purified by silica gel flash
chromatography (light petroleum/ethyl acetate/DCM 10 : 1 : 2)
to give 7e (63 mg, 221 mmol, 28 %) as a white solid. Mp 958C. R
(light petroleum/ethyl acetate/DCM, 10 : 1 : 2) 0.43. nmax (film)/
cmꢀ1 3170, 2924, 1673, 1619, 1498, 1455, 1426, 1385, 1362,
1290, 1254, 1223, 1170, 1141, 1121, 1090, 801, 752, 732, 691.
dH (CDCl3, 300 MHz) 2.24 (s, 3H), 3.05 (dd, J 16.3, 3.7, 1H),
3.21 (dd, J 11.3, 5.1, 1H), 4.23 (dq, J 10.1, 5.4, 1H), 4.90 (m,
1H), 6.64 (d, 3JH,H 7.4, 1H), 6.90 (m, 1H), 6.92 (m, 1H), 6.97 (tt,
J 7.4, 1.0, 1H), 7.24–7.32 (m, 4H), 11.13 (s, 1H). dC (CDCl3,
75 MHz) 15.5 (q), 29.7 (t), 68.5 (t), 77.2 (d), 107.5 (s), 114.6 (d,
2C), 117.4 (d), 121.5 (d), 125.5 (s), 129.6 (d, 2C), 135.8 (s),
137.1 (d), 158.1 (s), 160.6 (s), 169.5 (s). m/z (EI) 284 (100 %)
[Mþ], 266 (6), 200 (6), 191 (13), 190 (19), 177 (20), 174 (9), 173
(74), 163 (10), 162 (10), 161 (23), 151 (13), 149 (74), 148 (8),
121 (9), 113 (11), 91 (17); m/z (HR-MS, 70eV) 284.1047; calc.
for C17H16O4: 284.1049. Anal. calc. for C17H16O4 (284.3): C
71.82, H 5.67. Found: C 71.69, H 5.87 %.
Data agree with literature.[59]
Di(1-adamantyl)butylphosphinegold(I)
Bis(trifluoromethanesulfonyl)imidate (Au-PhosphineB)
A mixture of di(1-adamantyl)butylphosphinegold(I) chloride
(1.40 g, 2.38 mmol) and AgNTf2 (1.20, 2.38 mmol) was sus-
pended in DCM. The reaction mixture was stirred at room
temperature for 1 h, the solvent was evaporated, and the crude
product was dissolved in DCM. The mixture was then filtered
through a pad of Celite and the solvent was evaporated under
reduced pressure to give Au-PhosphineB as a white solid. Yield
99%. Mp 150–1708C. nmax (film)/cmꢀ1 2909, 2853, 1449, 1397,
1377, 1346, 1216, 1187, 1133, 1054, 965, 895, 823, 789, 709. dH
(CDCl3, 500 MHz)0.94 (t, J 7.2, 3H), 1.57(m, 2H), 1.76–1.79 (m,
16 H), 2.09–2.10 (m, 18H). dC (CDCl3, 125 MHz) 13.7 (q), 24.48
(t), 28.63–28.75 (d, adamantyl), 33.60 (s, adamantyl), 33.62 (t),
34.38 (t), 36.38 (t, adamantyl), 40.01 (d), 40.22 (d), 41.15 (t,
adamantyl). dP (202MHz, CDCl3) 69.18. m/z (HR-MS electro-
spray ionisation (ESI)) 555.2449 [Mþ]; calc. for C24H39AuP:
555.2455; m/z (HR-MS ESI) 279.9167, calc. for C2F6N1O4S2:
279.91. Anal. calc. for C26H39AuF6NO4PS2 (835.65): C 37.37,
H 4.70, N 1.68. Found C 37.46, H 4.78, N 1.70 %.
8-Hydroxy-7-methyl-3-[(5-methylfuran-2-yl)methyl]-
3,4-dihydro-1H-isochromen-1-one (7f)
Tris(tert-butyl)phosphinegold(I) Complex
(Au-PhosphineC)
According to General Procedure C, 6f (20 mg, 73 mmol)
was treated with di-tert-butyl-(20,40,60-triisopropyl-3,4,5,6-
tetramethylbiphenyl-2-yl)phospinegold(I) chloride (3 mg, 4 mmol)
and silver tetrafluoroborate (1 mg, 4 mmol) in 5 mL DCM. The
crude product was purified by silica gel flash chromatography
(light petroleum/ethyl acetate/DCM 15 : 1 : 1) to give 7f (7 mg,
26 mmol, 35 %) as a white solid. R (light petroleum/ethyl acetate/
DCM, 15 : 1 : 1) 0.49. nmax (film)/cmꢀ1 3438, 2948, 2924, 1671,
1621, 1426, 1253, 1173, 1138. dH (CD2Cl2, 300 MHz) 2.21 (s,
3H), 2.24 (s, 3H), 2.93 (d, 3JH,H 7.5, 2H), 3.01 (dd, J 15.1, 6.8,
1H), 3.15 (dd, J 15.1, 6.1, 1H), 4.80 (quin, 3JH,H 6.8, 1H) 5.91 (d,
3JH,H 2.7, 1H), 6.06 (d, 3JH,H 3.0, 1H), 6.61 (d, 3JH,H 7.5, 1H),
7.28 (d, 3JH,H 7.5, 1H), 11.17 (s, 1H). dC (CD2Cl2, 75 MHz) 12.8
(q), 14.7 (q), 31.7 (t), 33.1 (t), 77.7 (d), 105.8 (d), 107.2 (s), 108.2
(d), 116.9 (d), 124.6 (s), 136.1 (s), 136.4 (d), 147.7 (s), 151.2 (s),
159.9 (s), 169.6 (s). m/z (EI) 272 (55 %) [Mþ], 178 (6), 177 (48),
150 (10), 149 (100), 135 (7), 96 (10), 95 (26), 91 (10); m/z
(HR-MS, 70eV) 272.1055; calc. for C16H16O4: 272.1049.
(Chloro(tetrahydrothiophen)gold(I)) (500 mg, 1.56 mmol)
was dissolved in DCM and the phosphane ligand (333 mg,
1.56 mmol) was slowly added (,45 min) to this solution with
stirring. After 60 min, the solid was filtered off, washed with
DCM and dried under vacuum. Yield 99 %. Mp 2608C. nmax
(film)/cmꢀ1 2992, 2944, 2869, 1473, 1395, 1367, 1172, 1027,
931, 809, 747. dH (CDCl3, 500 MHz) 1.61 (s, 27H), dC (CDCl3,
125 MHz) 32.73 (q, 9C), 54.83, 54.05, 54.27 (s, 3C). dP (CDCl3,
202 MHz) 96.51. m/z (HR-MS ESI) 457.1097 [M þ Na]þ, calc.
for C12H27AuPClNa: 457.1102.
Di(1-adamantyl)benzylphosphinegold(I) Chloride
(Au-PhosphineD)
Tht-gold(I) chloride (408 mg, 1.27 mmol) was dissolved in
DCM and the phosphane ligand (500 mg, 1.27 mmol) was
slowly added (,45 min) to this solution with stirring. After
60 min, the solid was filtered off, washed with DCM and dried

496
A. S. K. Hashmi et al.
under vacuum. Yield 99 %. Mp 268–2708C. nmax (film)/cmꢀ1
2898, 2847, 1599, 1494, 1449, 1342, 1302, 1256, 1103, 1070,
1049, 971, 882, 834. dH (CDCl3, 500 MHz) 1.68–2.16 (m, 30H,
adamantyl), 3.26 (d, 2H, J 11.12), 7.23–7.29 (m, 1H), 7.31–7.32
(t, J 7.7, 2H), 7.57–7.59 (d, 2H, J 7.8). dC (CDCl3, 125 MHz)
24.3 (d), 28.27 (s), 28.34 (d), 31.83 (s, adamantyl), 36.20
(t, adamantyl), 40.81 (t, adamantyl), 127.03 (d), 128.87 (s),
130.63 (d, 2C, aromatic), 130.67 (d, 2C, aromatic). dP (CDCl3,
202 MHz) 67.74. m/z (HR-MS ESI) 647.1879 [M þ Na]þ; calc.
for C27H37AuClNaP: 647.1914.
Biphenyl-2-yl(dicyclohexyl)phosphinegold(I)
Chloride (Au-BiarylD)
According to General Procedure D, (tht)AuCl (64.1 mg,
0.2 mmol) and phosphine (70.1 mg, 0.2 mmol) were stirred in
DCM. Au-BiarylD (119 mg, 203 mmol, quant.) was obtained as
a white powder. dH (CDCl3, 250 MHz,) 1.01–2.02 (m, 22 H),
7.14–7.20 (m, 2 H), 7.27–7.34 (m, 1 H), 7.40–7.59 (m, 5 H),
7.67–7.77 (m, 1 H). dP (CDCl3, 101 MHz) 45.14.
Dicyclohexyl(20-methylbiphenyl-2-yl)phosphinegold(I)
Chloride (Au-BiarylE)
Biphenyl-2-yl-di-tert-butylphosphinegold(I) NTf2 Salt
According to General Procedure D, (tht)AuCl (64.13 mg,
0.2 mmol) and phosphine (72.90 mg, 0.2 mmol) were stirred in
DCM. Au-BiarylE (123.86 mg, 0.2 mmol, quant.) was obtained
as a white powder. Mp 260–2638C. nmax (KBr)/cmꢀ1 3056,
2928, 2851, 1628, 1467, 1448, 1004, 853, 755, 723, 669, 542. dH
(CDCl3, 500 MHz,) 1.04–1.40 (m, 10 H), 1.50–1.89 (m, 10 H),
1.90–1.99 (m, 2 H), 1.96 (s, 3 H), 7.00 (dd, J 7.5, J 1.1, 1 H),
7.22–7.26 (m, 2 H), 7.32 (d, 7.7, 1 H), 7.44–7.55 (m, 3 H), 7.60
(td, J 8.7, J 1.4, 1 H). dC (CDCl3,125 MHz) 20.97 (q), 25,74 (t),
25.83 (t), 26.42 (t), 26.60 (t), 26.84 (t), 26.91 (t), 28.93 (t), 29.58
(Au-BiarylA)
A mixture of biphenyl-2-yldi-tert-butylphosphinegold(I)
chloride (970 mg, 1.83 mmol) and AgNTf2 (922 mg,1.83 mmol)
was suspended in DCM. The reaction mixture was stirred at RT
for 1 h, the solvent was evaporated, and the crude product was
dissolved in DCM. The mixture was then filtered through a pad
of Celite, and the solvent was evaporated under reduced pressure
to give Au-BiarylA as a white solid. Yield 98 %. nmax (film)/
cmꢀ1 3423, 2955, 2187, 1470, 1442, 1393, 1373, 1184, 1125,
1059, 997, 956, 884, 826, 807, 774, 751, 697. dH (CDCl3,
500 MHz) 1.44 (d, J 15.5, 18H), 7.19 (dd, J 7.57 and 2.22,
2H), 7.31–7.34 (m, 1H), 7.53–7.66 (m, 5H), 7.91 (t, J 7.31Hz,
1H). dC (CDCl3, 125 MHz) 30.70 (q, 6C), 38.25 (s), 38.46 (s),
126.86 (d, 2C), 127.90 (d, 3C), 129.06 (d, 2C), 129.45 (d, 2C),
131.13 (s, 2C), 180.52 (s). dP (CDCl3, 202 MHz) 57.75. m/z
(HR-MS ESI) 495.1510 [Mþ] ; calc. for C20H27AuP: 495.1516.
1
(t), 30.87 (t), 30.96 (t), 35.38 (d), 37.49 (d), 125.12 (s, JC,P
51.7), 125.57 (d), 127.47 (d, 3JC,P 7.7), 128.77 (d), 129.94 (d),
131.08 (d, 4JC,P 1.9), 131.38 (d), 132.58 (d, 3JC,P 7.9), 132.84 (d,
4JC,P 4.3), 135.64 (s), 140.87 (s, 3JC,P 6.2),149.16 (s, 2JC,P 12.8).
dP (CDCl3, 202 MHz) 38.2. m/z (fast atom bombardment
(FAB)þ) 619.2 [M þ Na]þ, 596.2 [Mþ], 561.2 [Mþ – Cl]. Anal.
calc. for C25H33AuClP (596.92): C 50.30, H 5.57, Cl 5.94,
P 5.19. Found: C 50.22, H 5.67, Cl 5.73, P 5.03 %.
2-(Di-tert-butylphosphino)-1,10-biphenylgold(I)
2-(Dicyclohexylphosphino)-20-(N,N-dimethylamino)-
Chloride (Au-BiarylB)
1,10-biphenylgold Chloride (Au-BiarylF)
According to General Procedure D, (tht)AuCl (64 mg,
200 mmol) was treated with 2-(di-tert-butylphosphino)-1,10-
biphenyl (60 mg, 200 mmol) in 1 mL DCM. Au-BiphenylB
(105 mg, 198 mmol, 99 %) was obtained as a white solid. nmax
(film)/cmꢀ1 3443, 3423, 2928, 2852, 1627, 1447, 748. dH
According to General Procedure D, (tht)AuCl (160 mg,
500 mmol) was treated with 2-(dicyclohexylphosphino)-20-
(N,N-dimethylamino)-1,10-biphenyl (197mg, 500 mmol) in
10mL DCM. Au-BiarylF (309mg, 495 mmol, 99%) was
obtained as a white solid. Mp 190–1938C (decomp.). nmax
(KBr)/cmꢀ1 3434, 2961, 1629, 1471, 1174, 755. dH (CD2Cl2,
500MHz) 7.59 (d, 3JH,H 7.8, 1H), 7.54 (t, 3JH,H 7.4, 1H), 7.46 (t,
3JH,H 7.5, 1H), 7.42 (t, 3JH,H 7.5, 1H), 7.35 (d, 3JH,H 7.6, 1H), 7.07
(d, 3JH,H 8.2, 1H), 7.04 (t, 3JH,H 7.4, 1H), 6.99 (d, 3JH,H 7.2, 1H),
2.79 (m, 1H), 2.47 (s, 6H), 2.34 (tt, J 12.0, 3.0, 1H), 1.99–2.10 (m,
3H), 1.86–1.92 (m, 1H), 1.66–1.81 (m, 5H), 1.59 (dq, J 12.4, 3.3,
2H), 1.06–1.43 (m, 9H). dC (CD2Cl2, 125 MHz) 25.3 (t), 25.4 (t),
26.2 (t, 2C), 26.3 (t), 26.4 (t), 28.6 (t), 29.7 (t), 30.1 (t), 30.6 (t),
35.3 (d), 37.5 (d), 43.1 (q, 2C), 119.3 (d), 121.2 (d), 125.2 (s),
126.5 (d), 128.7 (d), 130.4 (d), 131.1 (d), 132.1 (d), 133.1 (d),
134.6 (s), 148.1 (s), 151.0 (s). dP (CD2Cl2, 202 MHz) 39.5. m/z
(FABþ) 627 (20 %) [Mþ, 37Cl], 626 (21), 625 (49) [Mþ, 35Cl]),
624 (12), 591 (29), 590 (100) [(M – Cl)þ], 589 (17), 588 (21), 574
3
(CDCl3, 300 MHz) 1.40 (d, J 15.6, 18H), 7.14 (d, JH,H 7.3,
2H), 7.28 (m, 1H), 7.38 (t, 3JH,H 7.5, 2H), 7.50 (m, 3H), 7.89 (t,
3JH,H 7.2, 1H). dC (CD2Cl2, 75 MHz) 30.1 (q, 3C), 30.2 (q, 3C),
37.0 (s), 37.4 (s), 126.2 (d), 127.4 (d), 128.0 (2C), 128.8 (d),
130.0 (d), 132.6 (s), 132.7 (d), 133.3 (d), 142.0 (s), 149.6 (s). dP
(CD2Cl2, 122 MHz) 60.0.
Di-tert-butyl-(20,40,60-triisopropyl-3,4,5,6-
tetramethylbiphenyl-2-yl)phospinegold(I) Chloride
(Au-BiarylC)
Tht-gold(I) chloride (100 mg, 0.31 mmol) was dissolved in
DCM and the phosphane ligand (150 mg, 0.31 mmol) was
slowly added (,45 min) to this solution with stirring. After
60 min, the solid was filtered off, washed with DCM and dried
under vacuum. Yield 99 %. nmax (film)/cmꢀ1 3436, 2960, 2925,
2867, 1754, 1608, 1460, 1392, 1383, 1362, 1313, 1250, 1164,
1067, 1023, 875, 770, 608, 536, 510. dH (CDCl3, 500 MHz) 0.79
(d, J 6.5, 6H), 1.22 (d, J 6.8, 6H), 1.31 (d, J 6.9, 6H), 1.44 (s, 9H),
1.47 (s, 9H), 2.17 (s, 6H), 2.24 (s, 3H), 2.28–2.34 (sept, J 6.9,
6.8, 2H), 2.54 (s, 3H), 2.89–2.95 (sept, J 6.5, 1H), 6.97 (s, 2H).
dC (CDCl3, 125 MHz) 17.30 (q), 17.77 (q, 2C), 22.25 (q), 24.65
(q, 2C), 25.07 (q, 2C), 25.19 (q, 2C), 28.02 (d), 30.02 (s, 2C),
30.67 (d), 33.42 (s, 6C), 34.23 (d), 122. 53 (d, 2C), 128.00 (s),
140.22 (s), 145.74 (s, 2C), 150.24 (s). dP (CDCl3, 202 MHz)
77.00. m/z (HR-MS ESI) 735.3131 [MþNa]þ; calc. for
C33H53AuClNaP: 735.3137.
(12), 506 (6) m/z (HR-MS, 70eV) 625.1939; calc. for
35
C26H ClNPAu: 625.1921;m/z590.2238;calc. forC26H36NPAu:
36
590.2251. Anal. calc. for C26H36ClNPAu (625.96): C 49.89,
H 5.80, N 2.24. Found: C 50.29, H 6.03, N 2.18%.
Dicyclohexyl(20,60-dimethoxybiphenyl-2-yl)
phosphinegold Chloride (Au-BiarylG)
According to General Procedure D, (tht)AuCl (64.13 mg,
0.2 mmol) and phosphine (82.11 mg, 0.2 mmol) were stirred in
DCM. Au-BiarylG (134 mg, 0.21 mmol, quant.) was obtained as
a white powder. dH (CDCl3, 250 MHz,) 1.16–1.46 (m, 7 H),
1.60–1.87 (m, 8 H), 1.90–2.23 (m, 7 H), 3.70 (s, 6 H), 6.66

Coumarins
497
(d, J 8.4, 2 H), 7.16–7.25 (m, 1 H), 7.45–7.60 (m, 4 H). dP
(CDCl3, 101 MHz) 39.83.
in DCM. Au-BiarylK (224 mg, 0.3 mmol, quant.) was obtained
as a colourless oil. nmax (KBr)/cmꢀ1 3423, 2930, 2851, 1631,
1451, 1399, 1228, 1100, 1020, 595. m/z (HR-MS ESI) 721.1224
[M – Na]ꢀ; calc. for C26H34AuClO5SP: 721.1219.
2-(Dicyclohexylphosphino)-20,60-(diisopropoxy)-1,10-
biphenylgold(I) Chloride (Au-BiarylH)
Di-tert-butyl(20-methylbiphenyl-2-yl)phosphinegold(I)
Chloride (Au-BiarylL)
According to General Procedure D, (tht)AuCl (160 mg,
500 mmol) was treated with 2-(dicyclohexylphosphino)-20,60-
diisopropyl-1,10-biphenyl (233 mg, 500 mmol) in 10 mL DCM.
Au-BiarylH (346 mg, 495 mmol, 99 %) was obtained as a white
solid. Mp 180–1838C (decomp.). nmax (KBr)/cmꢀ1 3431, 2974,
2928, 2852, 1626, 1594, 1459, 1383, 1248, 1116, 1064, 772,
According to General Procedure D, (tht)AuCl (64.1 mg,
0.2 mmol) and phosphine (62.5 mg, 0.2 mmol) were stirred in
DCM. Au-BiarylL (108 mg, 199 mmol, 99 %) was obtained as a
white powder. Mp 273–2758C. nmax (KBr)/cmꢀ1 3060, 2998,
2970, 2864, 1635, 1472, 1464, 1427, 1390, 1367, 1174, 810,
774, 754, 739, 723. dH (CDCl3, 300 MHz,) 1.41 (d, JH,P 15.5,
9H), 1.43 (d, JH,P 15.5, 9H), 2.02 (s, 3 H), 6.98 (dd, J 7.6, 1.1,
1H), 7.17–7.28 (m, 2H), 7.32 (d, J 7.7, 1H), 7.44–7.57 (m, 3H),
7.87 (dt, J 7.6, 1.5, 1H). dC (CDCl3,75 MHz) 20.80 (s), 30.78 (q,
3
727. dH (CD2Cl2, 500 MHz) 1.01 (d, JH,H 6.0, 6H), 1.18 (d,
3JH,H 6.0, 6H), 1.20–1.37 (m, 8H), 1.44 (dq, J 12.4, 3.4, 2H),
1.63–1.76 (m, 6H), 1.80 (m, 2H), 2.01 (m, 2H), 2.18 (tt, J 12.0,
3.0, 2H), 4.48 (sept, 3JH,H 6.0, 2H), 6.58 (d, 3JH,H 8.4, 2H), 7.08
(d, 3JH,H 7.6, 1H), 7.35 (t, 3JH,H 8.4, 1H), 7.42 (t, 3JH,H 7.6, 1H),
3
3
2
1
2JC,P 6.4, 3 C), 31.59 (q, JC,P 6.8, 3 C), 37.98 (s, JC,P 26.0),
38.07 (s, 1JC,P 25.9), 125.46 (d), 126.73 (d, 3JC,P 6.9), 126.90 (s,
1JC,P 45.0), 128.73 (d), 130.25 (d), 131.00 (d, 4JC,P 2.3), 131.33
(d), 133.43 (d, 3JC,P 7.7), 133.96 (d, 4JC,P 2.9), 135.52 (s), 141.28
(s, 3JC,P 6.4),149.71 (s, 2JC,P 13.9). dP (121 MHz, CDCl3) 59.79.
m/z (FABþ) 567.2 [M þ Na]þ, 544.2 [Mþ], 509.3 [Mþ – Cl].
Anal. calc. for C21H29AuClP (544.85): C 46.29, H 5.36, Cl 6.51,
P 5.68. Found C 46.18, H 5.31, Cl 6.71, P 5.68 %.
7.48 (t, JH,H 7.4, 1H), 7.53 (d, JH,H 7.7, 1H). dC (CD2Cl2,
125 MHz) 21.3 (q, 2C), 21.9 (q, 2C), 25.4 (t, 2C), 26.1 (t, 2C),
29.4 (t, 2C), 30.4 (t, 2C), 36.1 (d, 4C), 69.7 (d, 2C), 105.9 (d, 2C),
121.0 (s), 126.1 (d), 127.0 (s), 128.9 (d), 129.9 (d), 131.2 (d),
132.8 (d), 143.4 (s), 155.9 (s, 2C). dP (CD2Cl2, 202 MHz) 39.1.
m/z (FABþ) 700 (9 %) [Mþ, 37Cl], 699 (8), 698 (23) [Mþ, 35Cl]),
665 (6), 664 (33), 663 (100) [(M – Cl)þ], 662 (15), 661 (6), 659
(7), 621 (6), 620 (6), 619 (12), 579 (8). m/z (HR-MS, 70eV) 698.
35
2330; calc. for C30H ClO2PAu: 698.2355; m/z 663.2658; calc.
43
2-(Di-tert-butylphosphino)-20-(N,N-dimethylamino)-
for C30H43O2PAu: 663.2666. Anal. calc. for C30H43O2ClPAu
(699.05): C 51.54, H 6.20, Cl 5.07, P 4.43. Found: C 51.50,
H 6.28, Cl 4.95, P 4.44 %.
1,10-biphenylgold(I) Chloride (Au-BiarylM)
According to General Procedure D, (tht)AuCl (96 mg,
300 mmol) was treated with 2-(di-tert-butylphosphino)-20-
(N,N-dimethylamino)-1,10-biphenyl (102 mg, 300 mmol) in 5 mL
DCM. Au-BiarylM (170 mg, 297 mmol, 99 %) was obtained as a
white solid. Mp 250–2528C. nmax (KBr)/cmꢀ1 3442, 2996, 2773,
1628, 1494, 1472, 1172, 1053, 946, 761, 749. dH (CD2Cl2,
500 MHz) 1.23 (s, 9H), 1.52 (s, 9H), 2.45 (s, 6H), 6.97 (d, 3JH,H
7.5, 1H), 7.04 (t, 3JH,H 7.4, 1H), 7.08 (d, 3JH,H 8.2, 1H), 7.31 (d,
3JH,H 7.7, 1H), 7.45 (m, 2H), 7.55 (t, 3JH,H 7.5, 1H), 7.86 (d, 3JH,
2-Cyclohexylphosphino-20,40,60-triisopropyl-1,10-
biphenylgold(I) Chloride (Au-BiarylI)
According to General Procedure D, (tht)AuCl (96 mg,
300 mmol) was treated with 2-cyclohexylphosphino-20,40,60-
triisopropyl-1,10-biphenyl (143 mg, 300 mmol) in 5 mL DCM.
Au-BiarylI (211 mg, 297 mmol, 99 %) was obtained as a white
solid. Mp 207–2088C. nmax (KBr)/cmꢀ1 3440, 2957, 2929, 2854,
1629, 1609, 1463, 1448, 1382, 1361, 770. dH (CD2Cl2,
8.0, 1H). dC (CD2Cl2, 125 MHz) 29.5 (q), 30.9 (q), 37.0 (s),
H
3
500 MHz) 0.92 (d, JH,H 6.7, 6H), 1.19–1.25 (m, 5H), 1.28
(d, 3JH,H 6.9, 6H), 1.34 (d, 3JH,H 6.9, 7H), 1.47 (dq, J 12.3, 3.4,
2H), 1.66 (m, 2H), 1.75–1.84 (m, 6H), 1.91 (m, 1H), 2.06–2.14
37.5 (s), 43.2 (q), 120.5 (d), 121.5 (d), 126.4 (s), 128.6 (d), 130.4
(d), 130.9 (s), 133.6 (d), 134.0 (d), 136.1 (s), 148.5 (s), 150.9 (s).
dP (CD2Cl2, 202 MHz) 62.0. m/z (FABþ) 575 (24 %) [Mþ, 37Cl],
573 (63), [Mþ, 35Cl]), 572 (9), 539 (24), 538 (100), 537 (11).
m/z (HR-MS, 70eV) 573.1616; calc. for C22H32N35ClPAu:
573.1626.
3
(m, 4H), 2.25 (sept, JH,H 6.8, 2H), 2.79 (m, 1H), 2.94 (sept,
3JH,H 6.9, 1H), 7.06 (s, 2H), 7.22 (m, 1H), 7.50 (m, 2H), 7.63 (m,
1H). dC (CD2Cl2, 125 MHz) 22.4, 23.7, 25.0, 25.3 (t), 26.2 (t),
26.5 (t), 29.8 (t), 30.4, 34.0, 36.8, 121.1 (d), 126.7 (d), 130.0 (d),
131.9 (d), 133.3 (d), 145.3 (s), 146.9 (s), 149.5 (s). dP (CD2Cl2,
202 MHz) 35.8. m/z (FABþ) 710 (1 %) [Mþ, 37Cl], 708 (1),
2-(Di-tert-butylphosphino-20,40,60-triisopropyl-1,10-
biphenylgold(I) Chloride (Au-BiarylN)
[Mþ, 35Cl]), 673 (100) [(M – Cl)þ], 657 (9), 655 (6). m/z
According to General Procedure D, (tht)AuCl (76 mg,
240 mmol) was treated with di-tert-butyl-phosphino-20,40,60-
triisopropylbiphenyl (100 mg, 240 mmol) in 7 mL DCM.
Au-BiarylN (158 mg, 238 mmol, 99 %) was obtained as a white
solid. nmax (KBr)/cmꢀ1 3054, 2958, 2865, 1609, 1458, 1425,
1383, 1360, 1169, 1098, 1023, 770. dH (CD2Cl2, 300 MHz) 0.90
35
(HR-MS, 70eV) 708.2919; calc. for C33H ClPAu: 708.2926.
49
Sodium 2-Cyclohexylphosphino-20,60-diisopropyl-40-
sulfonato-1,10-biphenylgold(I) Chloride (Au-BiarylJ)
According to General Procedure D, (tht)AuCl (64.1 mg,
0.20 mmol) and phosphine (107 mg, 0.20 mmol) were stirred
in DCM. Au-BiarylJ (159 mg, 0.2 mmol, quant.) was obtained as
a yellowish oil. nmax (KBr)/cmꢀ1 3400, 2929, 2853, 1635, 1464,
1197, 1042, 772, 646. m/z (HR FABþ) 769.1892 [M þ H]þ; calc.
for C30H43AuClO3SPNa: 769.1922.
3
3
3
(d, JH,H 6.64, 6H), 1.27 (d, JH,H 6.8, 6H), 1.34 (d, JH,H 6.9,
6H), 1.38 (s, 9H), 1.43 (s, 9H), 2.35 (sept, 3JH,H 6.7, 2H), 2.94
(sept, 3JH,H 6.9, 1H), 7.05 (s, 2H), 7.28 (m, 1H), 7.50 (m, 2H),
7.89 (m, 1H). dC (CD2Cl2, 75 MHz) 23.1 (q), 24.5 (q), 26.2 (q),
31.2 (d), 31.4 (q), 31.5 (q), 34.7 (d), 38.4 (s) 38.8 (s), 122.1 (d),
126.8 (d, J 6.9), 128.3 (d), 128.9 (d), 130.6 (d, J 2.4), 135.0
(d, J 3.1), 135.3 (d, J 8.1), 146.3 (s, J 1.4), 148.6 (s), 150.4 (s). dP
(CD2Cl2, 122 MHz) 58.76. m/z (EI) 658 (2) [Mþ], 656 (4 %)
[Mþ], 621 (53), 620 (100), 521 (6), 423 (9), 382 (12), 381(29),
269 (7), 267 (11), 201 (5). m/z (HR-MS, 70eV) 656.2607; calc.
Sodium 2-Cyclohexylphosphino-20,60-dimethoxy-30-
sulfonato-1,10-biphenylgold(I) Chloride (Au-BiarylK)
According to General Procedure D, (tht)AuCl (96.0 mg,
0.30 mmol) and phosphine (154 mg, 0.30 mmol) were stirred

498
A. S. K. Hashmi et al.
for C29H45PAu35Cl: 656.2613. m/z (HR-MS, 70eV) 658.2569;
calc. for C29H45PAu37Cl: 658.2597.
1-(2-Methoxyphenyl)-2-(dicyclohexylphosphino)
pyrrolegold(I) Chloride (Au-BiarylR)
According to General Procedure D, (tht)AuCl (87 mg,
270 mmol) was treated with 1-(2-methoxyphenyl)-2-(dicyclo-
hexylphosphino)pyrrole (100 mg, 270 mmol) in 10 mL DCM.
Concentration yielded a white powder. Crystals were obtained
by slow evaporation of DCM at RT. Mp 206–2078C (decomp.).
1,10-Binaphthalen-2-yl(di-tert-butyl)phosphinegold(I)
Chloride (Au-BiarylO)
According to General Procedure D, (tht)AuCl (80.0 mg,
0.2 mmol) and phosphine (64.1 mg, 0.2 mmol) were stirred in
DCM. Au-BiarylO (127 mg, 0.2 mmol, quant.) was obtained as a
white powder. Mp 282–2858C (decomp.) nmax (KBr)/cmꢀ1 3060,
2556, 2898, 1473, 1367, 1170, 823, 802, 780, 772, 749. dH
(CDCl3, 300 MHz) 1.42 (d, JH,P 15.6, 9 H), 1.45 (d, JH,P 15.4, 9
H), 6.96 (t, J 9.7, 2 H), 7.19–7.25 (m, 2 H), 7.32 (dd, J 7.1, J 1.0, 1
H), 7.43–7.62 (m, 3 H), 7.89–8.05 (m, 4 H), 8.23(d, J 8.3, 1 H). dC
(CDCl3,75 MHz) 30.92 (q, 2JC,P 6.5, 3 C), 31.82 (q, 2JC,P 7.0, 3
C), 38.03 (s, 1JC,P 25.3), 38.25 (s, 1JC,P 25.6), 124.97 (d), 125.47
(s, 1JC,P 45.9), 126.12 (d), 126.18 (d), 126.26 (d), 127.16 (d, 4JC,P
1.1), 127.43 (d, 3JC,P 7.1), 127.69 (d), 128.29 (d), 128.64 (d, 4JC,P
n
max (KBr)/cmꢀ1 3449, 2927, 2850, 1599, 1513, 1448, 749, 727.
dH (CD2Cl2, 300 MHz) 1.25 (m, 10H), 1.80 (m, 11H), 2.14
(m, 1H), 3.77 (s, 3H), 6.43 (m, 1H), 6.66 (m, 1H), 6.92 (m, 1H),
7.05 (m, 1H), 7.18 (dd, J 7.9 and 1.8, 1H), 7.55 (dt, J 8.3 and 1.8,
1H). dC (CD2Cl2, 75 MHz) 26.25, 26.78, 26.87, 26.95, 27.02,
28.42, 29.81, 30.24, 30.73 (t, 10C), 36.25 (d, J 58.0, 1C), 36.77
(d, J 56.3, 1C), 55.74 (q, 1C), 109.85 (d, 1C), 113,06 (d, 1C),
119.91 (d, 1C), 120.87 (d, 1C), 130.16 (d, 1C), 130.67 (d, 1C),
156.10 (s, 1C). dP (CD2Cl2, 121 MHz) 23.56. m/z (HR-MS
ESIþ) 935.4106; calc. for C46H64Au1N2O2P2: 935.4109; m/z
1167.3243; calc. for C46H64Au2Cl1N2O2P2: 1167.3463.
4
1.5), 128.85 (d, JC,P 3.5) 129.36 (d), 129.49 (d), 129.72 (d),
133.53 (s), 134.10 (d, 4JC,P 1.9), 134.37 (s), 134.67 (s, 3JC,P 8.9),
136.24 (s, 3JC,P 7.9),147.87 (s, 2JC,P 13.1). dP (121 MHz, CDCl3)
62.05. m/z (FABþ) 653.2 [M þ Na]þ, 630.2 [Mþ], 595.2 [Mþ –
Cl]. Anal. calc. for C28H31AuClP (630.94): C 53.30, H 4.95, Cl
5.62, P 4.91. Found C 53.17, H 4.87, Cl 5.90, P 4.83 %.
Supplementary Material
Computational results on Au-BiarylF are available on the
Journal’s website.
References
20-(Diphenylphosphinyl)-N,N-dimethylbiphenyl-2-
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According to General Procedure D, (tht)AuCl (64.13 mg,
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2940, 2828, 1594, 1494, 1436, 1315, 1100, 945, 747, 722, 707,
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