Cobalt-catalyzed oxidative esterification of allylic/benzylic C(sp3)–H bonds

Article abstract of DOI:10.1016/j.tet.2017.04.002

A protocol for the cobalt-catalyzed oxidative esterification of allylic/benzylic C(sp³)–H bonds with carboxylic acids was developed in this work. Mechanistic studies revealed that C(sp³)–H bond activation in the hydrocarbon was the turnover-limiting step and the in-situ formed [Co(III)]Ot-Bu did not engage in hydrogen atom abstraction (HAA) of a C–H bond. This protocol was successfully incorporated into a synthetic pathway to β-damascenone that avoided the use of NBS.

Full text of DOI:10.1016/j.tet.2017.04.002

Accepted Manuscript
3
Cobalt-catalyzed oxidative esterification of allylic/benzylic C(sp )–H bonds
Tian-Lu Ren, Bao-Hua Xu, Sajid Mahmood, Ming-Xue Sun, Suo-Jiang Zhang
PII:
S0040-4020(17)30365-4
10.1016/j.tet.2017.04.002
TET 28603
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 19 February 2017
Revised Date: 30 March 2017
Accepted Date: 1 April 2017
Please cite this article as: Ren T-L, Xu B-H, Mahmood S, Sun M-X, Zhang S-J, Cobalt-catalyzed
3
oxidative esterification of allylic/benzylic C(sp )–H bonds, Tetrahedron (2017), doi: 10.1016/
j.tet.2017.04.002.
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to
our customers we are providing this early version of the manuscript. The manuscript will undergo
copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please
note that during the production process errors may be discovered which could affect the content, and all
legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT
Graphical Abstract
To create your abstract, type over the instructions in the template box below.
Fonts or abstract dimensions should not be changed or altered.
Cobalt-Catalyzed Oxidative Esterification of
Leave this area blank for abstract info.
Allylic/Benzylic C(sp3)−H Bonds
Tian-Lu Ren, Bao-Hua Xu, Sajid Mahmood, Ming-Xue Sun and Suo-Jiang Zhang

1
ACCEPTED MANUSCRIPT
Tetrahedron
journal homepage: www.elsevier.com
Cobalt-Catalyzed Oxidative Esterification of Allylic/Benzylic C(sp3)−H Bonds
Tian-Lu Rena,b , Bao-Hua Xua,b, , Sajid Mahmooda,b , Ming-Xue Sunc and Suo-Jiang Zhang a,b,
a Key Laboratory of Green Process and Engineering, Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex
Systems. Institute of Process Engineering, Chinese Academy of Sciences. Beijing 100190, P.R. China.
b School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
c. College of Chemistry and Chemical Engineering, Henan University. Henan Engineering Research Center of Resource & Energy Recovery from Waste. Kaifeng
475004, P.R. China.
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
A protocol for the cobalt-catalyzed oxidative esterification of allylic/benzylic C(sp3)−H bonds
with carboxylic acids was developed in this work. Mechanistic studies revealed that C(sp3)–H
bond activation in the hydrocarbon was the turnover-limiting step and the in-situ formed
[Co(III)]Ot-Bu did not engage in hydrogen atom abstraction (HAA) of a C–H bond. This
protocol was successfully incorporated into a synthetic pathway to β-damascenone that avoided
the use of NBS.
Available online
Keywords:
Cobalt
2009 Elsevier Ltd. All rights reserved
.
Oxidative esterification
C(sp3)–H bond activation
Carboxylic acid
Peroxide
———
Corresponding author. E-mail: bhxu@ipe.ac.cn (B. H. Xu), sjzhang@ipe.ac.cn (S. J. Zhang).
c On leave to Institute of Process Engineering.

2
Tetrahedron
ACCEPTED MANUSCRIPT
1. Introduction
resulted in markedly lower yields of the C–H esterification
product. In addition, a higher dosage of oxidant (2.0 equiv.) than
the theoretical amount (1.0 equiv.) was necessary to achieve an
optimal result (entries 10~12). Moreover, a moderate amount of
molecular sieves (MS, 4A, 165 mg) was found to be a requisite
additive, probably functioning as a desiccant in the reaction
(entry 13 vs. 10). Notably, a remarkably decreased yield of 3aa
was observed when the reaction time was extended from 18 h to
24 h (entry 14 vs. 13 and Figure S2). Under the optimized
conditions, 1a smoothly reacted with 2a (10.0 equiv.) in the
presence of CoCl2 (10 mol%) and DTBP (2.0 equiv.) in DCE (1
mL) at 120 °C to provide cyclohex-2-en-1-yl benzoate (3aa) in a
high yield of 82% (entry 14).
As a result of its wide applications, esterification is one of the
most fundamental and important reactions in organic chemistry
and in the synthesis of many natural products, pharmaceutical
molecules and fine chemicals.1 Consequently, considerable
attention has been directed towards the development of practical
and efficient strategies for ester synthesis.2 One highly efficient
approach is direct C(sp3)–H oxidative functionalization, thereby
converting alkanes into esters, either as the carboxylic or alkoxy
unit.3-5 However, the development of direct and selective
methods for alkane functionalization remains in its infancy due to
the low reactivity of C(sp3)–H bonds.6
Table 1. Development of the intermolecular oxidative esterification
of benzoic acid (2a) with cyclohexene (1a).a
Scheme 1. Cobalt-mediated direct esterification of C(sp3)–H bonds.
Yield (%)b
Entry
Cat.
Solvent
3aah
19
10
29
28
37
27
7
4ah
5ai
13
6
6ai
6
7
6
6
4
5
6
7
6
6
5
3
4
5
Various types of peroxides have been employed as stoichi-
ometric oxidants and often as the sources of oxygen functionality
in transition-metal3,4,7 or metal-free-catalyzed5,8 oxidative
esterification through a radical mechanism. Until now, copper
catalysis using peroxides as oxidants has been developed into a
well-defined methodology for C(sp3)–H bond esterification.3 In
principle, they are related to the classic Kharasch-Sosnovsky
reaction.9 In contrast, no study has been focused on cobalt, the
other reported Kharasch-Sosnovsky catalyst.9a The ability of
Co(II) complexes to dissociate peroxides, together with much
other experimental, mainly kinetic, evidence, has led to the
widely accepted opinion that their function is primarily to
generate free radicals.10 However, direct attack on the C(sp3)–H σ
bond by Co(III) species formed in situ may also be operative
(Scheme 1B).11,12 Most importantly, the behavior of Co(III)
complexes may be significantly different from that of Cu(II)
complexes in the oxidation of alkyl radicals. As previously
reported by Kochi,11b the former favors oxidative substitution
over oxidative elimination. Therefore, we considered to explore
the limits and scope of the cobalt-catalyzed oxidative
esterification of hydrocarbons with carboxylic acids in the
presence of a peroxide as the oxidant (Scheme 1A).
1
2
CoCl2
CoCl2
3
−
EAC
DCE
CH3CN
PhCF3
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
2
3
CoCl2
2
13
4
4
CoCl2
1
5
CoCl2
2
17
10
14
13
13
10
8
6
CoI2
1
7
Co(OH)2
Co(OAc)2
Co(acac)2
CoCl2
1
8
9
1
9
9
1
10c
11c,d
12c,e
13c,f
14c,f,g
46
21
17
74
82
4
CoCl2
3
CoCl2
2
6
CoCl2
1
8
CoCl2
1
6
a
Reaction conditions: 1a (0.5 mmol), 2a (10.0 equiv.), cat. (5 mol%), DTBP
b
(2.0 equiv.), solvent (1 mL), 100 °C, 24 h, under argon; Yields determined
d
by GC with biphenyl as an internal standard; c cat. (10 mol%); DTBP (1.5
equiv.); DTBP (1.0 equiv.); f MS (4A, 165 mg); 120 °C, 18 h; h Yield
e
g
i
calculated based on 1a; Yield calculated based on DTBP; DCE = 1,2-
dichloroethane, EAC = ethyl acetate.
We next examined the dependence of the C–H bond strength
of the substrate on the selectivity for C–H esterification over C–C
homocoupling when employing 2a and DTBP with 10 mol%
CoCl2 at 120 °C (Table 2). Substrates 2g (8%, entry 7), 2f (1%,
entry 6), 2e (79%, entry 5) and 2a (82%, entry 1) give the C–H
esterification product in yields that generally increase with
decreasing C–H bond strength. However, no ester was detected
by either GC-MS or NMR measurements in the case of
hydrocarbon R–H bonds of comparatively moderate strength,
such as 2d (entry 4), 2c (entry 3) and 2b (entry 2), under identical
conditions. Instead, the respective C–C homocoupling product
for 2d and 2c and 1,4-dihydronaphthalene/naphthalene for 2b
(formed upon the dehydrogenation of the starting material) were
the main products (Table S1). No significant improvement in the
selectivity of the ester was detected for the independent reaction
of 2g in PhCF3 (entry 8), thus disfavoring a negative effect
caused by the chlorinated solvent.
2. Results and discussion
First, we identified effective precatalysts and conditions for
the intermolecular esterification of unactivated C–H bonds by
evaluating the reactivity of benzoic acid (1a, 0.5 mmol) and
cyclohexene (2a, 10.0 equiv.) with various cobaltous salts (0~30
mol%) and t-BuOOt-Bu (DTBP). As shown in Table 1, the
desired allylic ester cyclohex-2-en-1-yl benzoate (3aa) was
produced, accompanied by a significant amount of [1,1'-
bi(cyclohexane)]-2,2'-diene (5a). In addition, side products
methyl benzoate (4a) and 3-methylcyclohex-1-ene (6a) were also
detected, the proportion of which varied with the conditions used.
The combination of CoCl2 and DTBP was crucial for catalysis
(entry 3), while other cobaltous salts provided reduced yields of
3aa (entries 6~9). Independently investigating the reaction
efficiency as a function of the catalyst amount indicated that a
certain loading of catalyst was required for high selectivity
towards the ester (entry 10 vs. 3 and Figure S1). For example,
introducing either less than 5 mol% or more than 15 mol% CoCl2

3
Table 2. Cobalt-catalyzed oxidative esterification of various C(sp3)–
Table 3. C(sp3)–H esterification of 2a with carboxylic acid
ACCEPTED MANUSCRIPT
H bonds with 2a.a
derivatives.a
O
O
O
Cl
O
O
O
R
n
3ia (n = 1), 65%c (63%d)
3ja (n = 2), 61%c (58%d)
3ka (n = 4), 61%c (58%d)
3aa (R = H), 81%b (80%d)
Cl
3ha, 42%c (41%d)
3ba (R = p-OMe), 80%b (78%d)
3ca (R = p-CN), 87%b (84%d)
3da (R = p-NO2), 89%b (87%d)
3ea (R = p-Cl), 87%b (85%d)
3fa (R = m-Cl), 74%b (72%d)
3ga (R = o-Cl), 25%b (22%d)
C−H BDE
Entry
R–H
Yield (%)b,c
O
[kcal mol−1]
O
O
R
O
1
2
2a
2b
2c
2d
2e
2f
82
83
84
86
87
90
97
97
83
86
3aa (82/80d)
3ab (N.D.)
3ac (N.D.)
3ad (N.D.)
3ae (79/78d)
3af (1)
3la (R = Me), 26%c
3ma (R = Et), 26%c
3na, 24%c (22%d)
3
O
O
O
4
O
O
O
X
5
HN
O
3oa (X = O), 79%c (76%d)
3pa (X = S), 83%c (80%d)
3ra, 0%c
3qa, 65%c (63%d)
6
7
2g
2g
2b
2d
3ag (8)
a
Reaction conditions: 1 (0.5 mmol), 2a (10.0 equiv.), CoCl2 (10 mol%),
DTBP (2.0 equiv.), DCE (1 mL), MS (4A, 165 mg), 120 °C, 18 h, under
8e
9f
3ag (3)
3ab (33/32d)
3ad (30/26d)
b
c
argon; Yields determined by GC with biphenyl as an internal standard;
10f
Yields determined by 1H NMR with CH2Br2 as an internal standard; d Isolated
yield.
a
Reaction conditions: 1a (0.5 mmol), 2 (10.0 equiv.), CoCl2 (10 mol%),
DTBP (2.0 equiv.), DCE (1 mL), MS (4A, 165 mg), 120 °C, 18 h, under
argon; b Yields determined by a combination of GC-MS (using the peak area
In these experiment, a slightly faster rate of decomposition of
DTBP with increasing CoCl2 loading was observed for the
reaction (Figure S3), indicating that an induced decomposition
occurred to concomitantly generate [CoIII]Ot-Bu and t-BuO•,
which was in agreement with Kochi’s observations.11b The
subsequent reaction pathway was highly dependent on the
reactivity of [CoIII]Ot-Bu since both the C–H σ bonds in
hydrocarbons and carbon radicals are potentially reactive in the
presence of cobaltic complexes.11,12
1
c
normalization method) and H NMR (with CH2Br2 as an internal standard);
d
e
Yields calculated based on 1a; Isolated yield; PhCF3 (1 mL) used as a
solvent; f 12 h; N.D. = not detected.
In addition, moderate yields of 3ab (32%) and 3ad (26%)
were generated when the reaction time was reduced to 12 h
(Table 2, entries 9 and 10). We speculated that those esters were
sensitive to the reaction conditions and readily decomposed over
time. The full conversion of 3ab/3ad (isolated) was detected by a
1
CoCl2
t-BuOOt-Bu
1/2 t-BuOOt-Bu
combination of GC-MS and H NMR after reaction for 18 h at
R1C(O)OR2 (3)
120 °C in the presence of CoCl2/DTBP, with none of the desired
compound formed. The same decomposition was found for 3aa,
albeit at a slower rate. After reaction for 18 h under identical
conditions, 40% of 3aa remained (Figure S4).
- Me2C(O)
R2H (2)
R2•
[CoIII]OC(O)R1
t-BuO•
[CoIII]Ot-Bu
t-BuO•
Me•
HAA
- t-BuOH
+ [CoIII]OC(O)R1
− CoCl2
A range of carboxylic acid derivatives (1) was then examined
in the coupling reaction with 2a under the optimized reaction
conditions (Table 3). The results demonstrated that electronic
variations in the substituents at the para-position of 1a did not
affect the reaction efficiency. The corresponding cyclohex-2-en-
1-yl benzoate substituted with methoxy, nitro, cyano and chloro
groups was obtained in satisfactory yields. In contrast, a
significant steric effect was observed when introducing
substituents into the meta- and ortho-positions. Taking chloro-
substituted benzoic acid as an example, the ester yield decreased
sharply with increased steric hindrance at the reactive site,
displaying an order of para- (85%) > meta- (72%) > ortho-
(22%). With the two meta-positions fully substituted by chloro
groups, a yield of only 41% of the ester was obtained. Aliphatic
carboxylic acids could also be employed as facile substrates that
provided the corresponding ester in acceptable yields. The
expected intramolecular esterification was not detected in the
case of either 1j or 1k. In fact, the self-esterification of 1j
proceeded poorly in the absence of 2a under identical conditions,
generating 5-phenyldihydrofuran-2(3H)-one in a yield of 21%
(Scheme S4). Finally, various heteroaromatic acids, with the
exception of piperidine-4-carboxylic acid, were found to be
tolerated in this catalytic system, and they afforded their
cyclohex-2-en-1-yl carboxylates in moderate yields.
+ R2•
R1C(O)OMe (4)
R2Me (6)
byproduct
R1C(O)OH (1)
t-BuOH
Scheme 2. Proposed catalytic cycle for cobalt-catalyzed oxidative
esterification of hydrocarbons with carboxylic acids.
To better illustrate the fate of the t-BuO• radical and
[Co(III)]Ot-Bu concomitantly formed upon the reaction of Co(II)
with DTBP in the catalytic process, we employed 2a as the single
substrate for oxidation. The reaction of DTBP (3.0 mmol) with
2a (5.0 equiv.) in the presence of CoCl2 (20 mol%) at 120 °C for
24 h gave 5a in a yield of 35%, along with a small amount of 6a
(Scheme S3). The desired ether, 3-(tert-butoxy)cyclohex-1-ene,
formed upon ligand transfer was not detected at all, suggesting
the limited reactivity of [Co(III)]Ot-Bu as a single electron
transfer reagent. Indeed, both competitive and independent
experiments revealed that the cobaltic salts formed in situ, such
as [Co(III)]Ot-Bu and [Co(III)]OC(O)Ph, did not engage in
hydrogen atom abstraction (HAA) of an R–H bond in a substrate
under these conditions (Table S2 and S3).
We therefore hypothesized that [Co(III)]Ot-Bu rapidly reacted
with the carboxylic acid to form [Co(III)]OC(O)R and t-BuOH,

4
Tetrahedron
while t-BuO• undergoes facile HAA with hydrocarbons to
effectively created a synthetic route to β-damascenone that
ACCEPTED MANUSCRIPT
generate a carbon radical (Scheme 2). Subsequently, this carbon
radical reacted with [Co(III)]OC(O)R, which released the ester
product and regenerated a [Co(II)] species to complete the
catalytic cycle.
avoided the use of NBS.
4. Experimental section
4.1. General procedure for C−H esterification of 2a with various
carboxylic acids (1)
O
CH3
H
H
H
A DCE solution (1 mL) was prepared under argon consisting
of carboxylic acids (0.5 mmol), 2a (512 µL, 5.0 mmol, 10.0
equiv.), CoCl2 (6.5 mg, 0.05 mmol, 10.0 mol%), DTBP (189 µL,
1.0 mmol, 2.0 equiv.), and molecular sieves (4A, 165.0 mg) in a
sealed reaction tube with a stirbar. The mixture was then heated
to 120oC and reacted for 18h, thereafter being filtered through
diatomite to remove the catalyst. The residue was extracted by
diethyl ether (3 × 5mL). Afterwards, the combined organic
filtrate was dried by Na2SO4 overnight and concentrated. The
respective ester was afforded through purification by column
chromatography on silica gel.
CH3
O
O
CoCl2 (10 mol%)
DTBP (2.0 equiv.)
3ae
2e
OH
or
or
+
DCE (1 mL)
4AMS, 120 oC
D
O
CD3
D
D
D
1a
D
D
D
D
0
1h
CD3
O
D
KIE = 1.9±0.5
D
D
D
2e-d10
D
3ae-d9
Scheme 3. Kinetic isotope effect study on competitive esterification
of 2e vs. 2e–d10.
4.2. General procedure for C−H esterification of various
hydrocarbons (2) with 1a.
Labeling experiments of the independent reactions of 1a and
2e vs. 2e-d10 were conducted in separated vessels to estimate the
kinetic isotope effect (KIE). In these experiments, the value of
the KIE was calculated from the initial rate of esterification of 2e
with 1a relative to that of 2e-d10 (Scheme 3 and Figure S7). The
obtained value was remarkably 1.9(5), indicating that the
cleavage of the benzyl C–H bond was the turnover-limiting step.
A DCE solution (1 mL) was prepared under argon consisting
of 1a (61.4 mg, 0.5 mmol), hydrocarbons (5.0 mmol, 10.0 equiv.),
CoCl2 (6.5 mg, 0.05 mmol, 10.0 mol%), DTBP (189 µL, 1.0
mmol, 2.0 equiv.), and molecular sieves (4A, 165.0 mg) in a
sealed reaction tube with a stirbar. The mixture was then heated
to 120oC and reacted for 18h, thereafter being filtered through
diatomite to remove the catalyst. The residue was extracted by
diethyl ether (3 × 5mL). Afterwards, the combined organic
filtrate was dried by Na2SO4 overnight and concentrated. The
respective ester was afforded through purification by column
chromatography on silica gel.
4.3. Procedure for synthesis of 3ah
A DCE solution (1 mL) was prepared under argon consisting
of 2h (96.6 mg, 0.5 mmol), 1a (67.5 mg, 0.55 mmol, 1.1 equiv.),
CoCl2 (6.5 mg, 0.05 mmol, 10.0 mol%), DTBP (189 µL, 1.0
mmol, 2.0 equiv.), molecular sieves (4A, 165.0 mg) in a sealed
reaction tube with a stirbar. The mixture was then heated to
120oC and reacted for 18h, thereafter being filtered through
diatomite to remove the catalyst. The residue was extracted by
diethyl ether (3 × 5mL). Afterwards, the combined organic
filtrate was dried by Na2SO4 overnight and concentrated, which
was purified by column chromatography on silica gel (petroleum
ether/ethyl acetate 30:1) and provided 3ah in a yield of 61%.
Scheme 4. Synthetic route to β-damascenone.
Encouragingly, the esterification of 2h at the allylic position
of the ring, rather than the linear one, proceeded smoothly using
this newly developed protocol, generating 3ah in a yield of 61%
when reacting 2h with a slight excess of 1a under the standard
reaction conditions (Scheme 4). Then, 3ah dehydrocarboxylated
readily using the conditions reported by Delmond,13 thereby
generating the desired product, β-damascenone, in a good yield
(74%). In contrast with the reported two-step dehydrogenation
method, requiring an initial oxidative bromination and a
subsequent dehydrobromination,14 we offer here a synthetic
pathway that avoids the use of N-Bromosuccinimide (NBS),
which has the potential to im-prove the product specification.
4.4. Procedure for synthesis of β-damascenon
A reaction tube was charged with 3ah (156.2 mg, 0.5 mmol),
toluene (10 mL). After the addition of TsOH (17.4 mg, 20mol%),
o
the reaction mixture was stirred at 50 C under argon for 12h.
The products were extracted by diethyl ether (3 × 5mL). The
combined organic extract was dried by Na2SO4 overnight and
concentrated, then purified by column chromatography on silica
gel (CH2Cl2) and provided β-damascenone in a yield of 74%.
3. Conclusions
In summary, we have introduced a cobalt-catalyzed oxidative
esterification of allylic/benzylic C(sp3)−H bonds with a variety of
carboxylic acids to produce the corresponding ester products. The
limitations of hydrocarbon structure were identified, which were
partially due to ester instability under the reaction conditions. We
speculated that the ester was significantly decarboxylated. We are
currently investigating this further for more solid evidence.
Mechanistic studies of this newly developed cobalt-catalyzed
oxidative esterification of allylic/benzylic C(sp3)−H bonds
indicated that the hydrocarbon C–H bond activation was the
turnover-limiting step, and the transient [Co(III)]Ot-Bu species
did not engage in HAA of a C−H bond. The developed method
4.5. NMR characterization of products
1
Table 2. 3aa: H NMR (600 MHz, CDCl3, 298 K): δ = 8.05
3
3
3
(ddm, JHH = 8.3 Hz, JHH = 1.3 Hz, 2H, o-Ph), 7.54 (ddm, JHH
=
=
7.6 Hz, 3JHH = 1.3 Hz, 1H, p-Ph), 7.43 (ddm, 3JHH = 8.3 Hz, 3JHH
7.6 Hz, 2H, m-Ph), 5.99 (m, 1H, =CH), 5.83 (m, 1H, =CH), 5.50
1
(m, 1H, OCH), 2.14 (dm, JHH = 19.1 Hz, 1H, CH2), 2.04 (dm,
1JHH = 19.1 Hz, 1H, CH2), 1.98 (m, 1H, CH2), 1.89 (m, 1H, CH2),
1.84 (m, 1H, CH2), 1.71 (m, 1H, CH2). 13C{1H} NMR (151 MHz,
CDCl3, 298 K): δ = 166.4 (C=O), 133.0 (p-Ph), 132.9 (=CH),

5
130.9 (i-Ph), 129.7 (m-/o-Ph), 128.4 (m-/o-Ph), 125.9 (=CH),
68.7 (OCH), 28.6, 25.1, 19.1 (CH2).
129.4 (i-Ph), 128.8 (o-/m-Ph), 125.6 (=CH), 69.1, (OCH), 28.5,
25.1, 19.0 (CH2).
ACCEPTED MANUSCRIPT
1
Table 2. 3ab: H NMR (600 MHz, CDCl3, 298 K): δ = 8.15
Table 3. 3fa: 1H NMR (600 MHz, CDCl3, 298 K): δ = 8.02 (s,
3
3
(d, JHH = 7.8 Hz, 2H, o-Ph), 7.62 (m, JHH = 7.8 Hz, 1H, p-Ph),
7.50 (t, 3JHH = 7.8 Hz, 2H, m-Ph), 7.46 (d, 3JHH = 7.2 Hz, 1H, m-
Ph), 7.34 (t, 3JHH = 7.8 Hz, 1H, m-Ph), 7.26 (q, 3JHH = 7.8 Hz, 2H,
1H, o-PhCl), 7.93 (dm, 3JHH= 7.9 Hz, 1H, o-/p-Ph), 7.51 (dm, 3JHH
3
3
= 8.7 Hz, 1H, o-/p-Ph), 7.37 (ddm, JHH = 8.7 Hz, JHH = 7.9 Hz,
1H, m-Ph), 6.02 (m, 1H, =CH), 5.82 (m, 1H, =CH), 5.50 (m, 1H,
OCH), 2.15 (dm, 1JHH = 18.0 Hz, 1H, CH2), 2.04 (dm, 1JHH = 18.0
Hz, 1H, CH2), 1.97 (m, 1H, CH2), 1.87 (m, 1H, CH2), 1.83 (m,
1H, CH2), 1.71 (m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3,
298 K): δ = 165.1 (C=O), 134.5 (i-Ph), 133.3, 132.9 (Ph/=CH),
132.7 (i-Ph), 129.8, 129.7, 127.9, 125.5 (Ph/=CH), 69.2 (OCH),
28.5, 25.1, 19.0 (CH2).
3
o-Ph), 6.36 (t, JHH = 4.2 Hz, 1H, OCH), 3.02(m, 1H, CH2),
2.89(m, 1H, CH2), 2.21(m, 2H, CH2), 2.16(m, 1H, CH2), 1.98(m,
1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ = 166.3
(C=O), 138.1 (Ph), 134.8 (Ph), 133.0 (Ph), 130.8 (Ph), 129.8
(Ph), 129.7 (Ph), 129.2 (Ph), 128.4 (Ph), 128.2 (Ph), 126.2 (Ph),
70.7 (OCH), 29.3 (CH2), 29.2 (CH2), 19.2 (CH2).
1
1
Table 2. 3ad: H NMR (600 MHz, CDCl3, 298 K): δ = 8.01
Table 3. 3ga: H NMR (600 MHz, CDCl3, 298 K): δ = 7.80
(d, 3JHH = 7.8 Hz, 2H, o-Ph), 7.47 (dd, 3JHH = 13.8 Hz, 3JHH = 7.8
(dm, JHH = 7.8 Hz, 1H, o-PhCO), 7.43 (dm, JHH= 8.4 Hz, 1H, m-
3
3
Hz, 2H, m-Ph), 7.36 (t, 3JHH = 7.2 Hz, 2H, m-Ph), 7.27 (m, 2H, o-
PhCl), 7.39 (ddm, JHH = 7.8 Hz, JHH = 7.0 Hz, 1H, m-Ph), 7.30
(ddm, 3JHH = 8.4 Hz, 3JHH = 7.0 Hz, 1H, p-Ph), 6.02 (m, 1H, =CH),
5.86 (m, 1H, =CH), 5.53 (m, 1H, OCH), 2.13 (dm, 1JHH = 17.9 Hz,
1H, CH2), 2.03 (dm, 1JHH = 17.9 Hz, 1H, CH2), 1.97 (m, 1H, CH2),
1.93 (m, 1H, CH2), 1.83 (m, 1H, CH2), 1.71 (m, 1H, CH2).
13C{1H} NMR (151 MHz, CDCl3, 298 K): δ = 165.6 (C=O),
133.7 (i-Ph), 133.4, 132.4, 131.4, 131.1 (Ph/=CH), 131.0 (i-Ph),
126.7, 125.4 (Ph/=CH), 69.6 (OCH), 28.4, 25.1, 19.0 (CH2).
3
3
1
3
3
Ph), 7.20 (m, H, p-Ph), 6.36 (dd, JHH = 6.6 Hz, JHH = 4.2 Hz,
1H, OCH), 3.14(m, 1H, CH2), 2.90(m, 1H, CH2), 2.59(m, 1H,
CH2), 2.20(m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298
K): δ = 166.6 (C=O), 144.5 (Ph), 141.2 (Ph), 132.9 (Ph), 130.5
(Ph), 129.8 (Ph), 129.0 (Ph), 128.4 (Ph), 126.8 (Ph), 125.8 (Ph),
124.9 (Ph), 79.0 (OCH), 32.6 (CH2), 30.4 (CH2).
1
Table 2. 3ae: H NMR (600 MHz, CDCl3, 298 K): δ = 8.10
(m, 2H, o-Ph), 7.56 (m, 1H, p-Ph), 7.47 (m, 2H, o-Ph), 7.45 (m,
Table 3. 3ha: 1H NMR (600 MHz, CDCl3, 298 K): δ = 7.90 (d,
2H, m-Ph), 7.33 (m, 2H, m-Ph), 7.32 (m, 1H, p-Ph), 6.15 (q, 3JHH
4JHH = 8.4 Hz, 2H, o-Ph), 7.53 (d, JHH= 8.4 Hz, 1H, p-Ph), 6.03
4
= 6.6 Hz, 1H, OCH), 1.69 (d, JHH = 6.6 Hz, 3H, CH3). 13C{1H}
(m, 1H, =CH), 5.81 (m, 1H, =CH), 5.50 (m, 1H, OCH), 2.15 (dm,
3
1
NMR (151 MHz, CDCl3, 298 K): δ = 165.9 (C=O), 141.9 (Ph),
133.0 (p-Ph), 130.7 (i-Ph), 129.8 (m-/o-Ph), 128.7 (m-/o-Ph),
128.5 (Ph), 128.0 (Ph),126.2 (Ph), 73.0 (OCH), 22.6 (CH3).
1JHH = 19.8 Hz, 1H, CH2), 2.05 (dm, JHH = 19.8 Hz, 1H, CH2),
1.97 (m, 1H, CH2), 1.88 (m, 1H, CH2), 1.83 (m, 1H, CH2), 1.72
(m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ =
164.0 (C=O), 135.3, 133.7, 132.7, 132.4, 128.2, 125.2 (Ph/=CH),
69.8 (OCH), 28.2, 25.0, 19.0 (CH2).
1
Table 3. 3ba: H NMR (600 MHz, CDCl3, 298 K): δ = 8.00
3
3
(dm, JHH= 9.0 Hz, 2H, Ph), 6.90 (dm, JHH= 9.0 Hz, 2H, Ph),
5.97 (m, 1H, =CH), 5.81 (m, 1H, =CH), 5.46 (m, 1H, OCH), 3.85
Table 3. 3ia: 1H NMR (600 MHz, CDCl3, 298 K): δ = 7.29 (m,
2H, m-Ph), 7.21 (m, 2H, o-Ph), 7.20 (m, 1H, p-Ph), 5.94 (m, 1H,
=CH), 5.69 (m, 1H, =CH), 5.26 (m, 1H, OCH), 2.96 (t, 3JHH = 7.7
1
(s, 3H, OCH3), 2.13 (dm, JHH = 18.4 Hz, 1H, CH2), 2.02 (dm,
1JHH = 18.4 Hz, 1H, CH2), 1.96 (m, 1H, CH2), 1.86 (m, 1H, CH2),
1.83 (m, 1H, CH2), 1.69 (m, 1H, CH2). 13C{1H} NMR (151 MHz,
CDCl3, 298 K): δ = 166.1 (C=O), 163.3 (i-PhOMe), 132.7 (o-/m-
Ph), 131.7 (=CH), 126.1(o-/m-Ph), 123.4 (i-PhC=O), 113.6 (=CH),
68.4(OCH), 55.5 (OCH3), 28.56, 25.1, 19.1 (CH2).
Hz, 2H, CH2C=O), 2.63 (tm, JHH = 7.7 Hz, 2H, CH2Ph), 2.08 (dm,
3
1JHH = 18.2 Hz, 1H, CH2), 1.98 (dm, JHH = 18.2 Hz, 1H, CH2),
1
1.84 (m, 1H, CH2), 1.71 (m, 1H, CH2), 1.68 (m, 1H, CH2), 1.62
(m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ =
172.7 (C=O), 140.7 (i-Ph), 132.8, 128.6, 128.5, 126.3, 125.8
(Ph/=CH), 68.2 (OCH), 36.4, 31.2, 28.4, 25.0, 19.0 (CH2).
Table 3, 3ja: 1H NMR (600 MHz, CDCl3, 298 K): δ = 7.28 (m,
2H, m-Ph), 7.19 (m, 1H, p-Ph), 7.18 (m, 2H, p-Ph), 5.95 (m, 1H,
=CH), 5.70 (m, 1H, =CH), 5.27 (m, 1H, OCH), 2.65 (m, 2H,
1
Table 3. 3ca: H NMR (600 MHz, CDCl3, 298 K): δ = 8.13
3
3
(dm, JHH= 8.4 Hz, 2H, Ph), 7.72 (dm, JHH= 8.4 Hz, 2H, Ph),
6.03 (m, 1H, =CH), 5.81 (m, 1H, =CH), 5.51 (m, 1H, OCH), 2.14
1
1
(dm, JHH = 17.7 Hz, 1H, CH2), 2.04 (dm, JHH = 17.7 Hz, 1H,
CH2), 1.97 (m, 1H, CH2), 1.89 (m, 1H, CH2), 1.82 (m, 1H, CH2),
1.71 (m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ
= 164.6 (C=O), 134.7 (i-PhC=O), 133.6 (=CH), 132.2 (o-/m-Ph),
130.2 (o-/m-Ph), 125.1 (=CH), 118.1 (i-PhCN), 116.3 (CN), 69.7,
(OCH), 28.4, 25.0, 18.9 (CH2).
1
CH2), 2.33 (m, 2H, CH2), 2.09 (dm, JHH = 18.9 Hz, 1H, CH2),
1.99 (dm, 1JHH = 18.9 Hz, 1H, CH2), 1.96 (m, 2H, CH2), 1.87 (m,
1H, CH2), 1.73 (m, 1H, CH2), 1.72 (m, 1H, CH2), 1.64 (m, 1H,
CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ = 173.3
(C=O), 141.6 (i-Ph), 132.8, 128.6, 128.5, 126.1, 125.9 (Ph/=CH),
68.0 (OCH), 35.3, 34.2, 26.8, 28.5, 25.0, 19.0 (CH2).
1
Table 3. 3da: H NMR (600 MHz, CDCl3, 298 K): δ = 8.27
3
3
(dm, JHH = 9.0 Hz, 2H, Ph), 8.21 (dm, JHH= 9.0 Hz, 2H, Ph),
6.05 (m, 1H, =CH), 5.83 (m, 1H, =CH), 5.54 (m, 1H, OCH), 2.16
1
Table 3, 3ka: H NMR (600 MHz, CDCl3, 298 K): δ = 7.28
1
1
(dm, JHH = 17.9 Hz, 1H, CH2), 2.06 (dm, JHH = 17.9 Hz, 1H,
CH2), 2.00 (m, 1H, CH2), 1.91 (m, 1H, CH2), 1.84 (m, 1H, CH2),
1.73 (m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ
= 164.4 (C=O), 150.6 (i-PhNO2), 136.4 (i-PhC=O), 133.8 (o-/m-Ph),
130.8 (=CH), 125.1 (o-/m-Ph), 123.6 (=CH), 69.9 (OCH), 28.4,
25.0, 18.9 (CH2).
(m, 2H, m-Ph), 7.18 (m, 1H, p-Ph), 7.17 (m, 2H, o-Ph), 5.95 (m,
1H, =CH), 5.69 (m, 1H, =CH), 5.27 (m, 1H, OCH), 2.62 (m, 2H,
1
CH2), 2.30 (m, 2H, CH2), 2.09 (dm, JHH = 16.8 Hz, 1H, CH2),
1.99 (dm, 1JHH = 16.8 Hz, 1H, CH2), 1.86 (m, 1H, CH2), 1.72 (m,
2H, CH2), 1.66 (m, 5H, CH2), 1.38 (m, 2H, CH2). 13C{1H} NMR
(151 MHz, CDCl3, 298 K): δ = 173.6 (C=O), 142.7 (i-Ph), 132.7,
128.5, 128.4, 125.9, 125.8 (Ph/=CH), 68.0 (OCH), 35.9, 34.7,
31.2, 28.9, 25.1, 28.5, 25.0, 19.0 (CH2).
1
Table 3. 3ea: H NMR (600 MHz, CDCl3, 298 K): δ = 7.98
3
3
(dm, JHH = 9.0 Hz, 2H, Ph), 7.40 (dm, JHH = 8.4 Hz, 2H, Ph),
6.01 (m, 1H, =CH), 5.82 (m, 1H, =CH), 5.50 (m, 1H, OCH), 2.15
(dm, JHH = 17.8 Hz, 1H, CH2), 2.04 (dm, JHH = 17.8 Hz, 1H,
CH2), 1.97 (m, 1H, CH2), 1.87 (m, 1H, CH2), 1.83 (m, 1H, CH2),
1.71 (m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ
= 165.5 (C=O), 139.3 (i-Ph), 133.3 (=CH), 131.1 (o-/m-Ph),
Table 3, 3na: 1H NMR (600 MHz, CDCl3, 298 K): δ = 7.69 (d,
3JHH= 16.2 Hz, 1H, =CHC=O), 7.52 (m, 2H, m-Ph), 7.38 (m, 1H, p-
1
1
Ph), 7.37 (m, 2H, o-Ph), 6.45 (d, JHH= 16.2 Hz, 1H, =CHPh),
3
6.00 (m, 1H, =CHcyclo), 5.79 (m, 1H, =CHcyclo), 5.41 (m, 1H,
OCH), 2.13 (dm, 1JHH = 20.0 Hz, 1H, CH2), 2.02 (dm, 1JHH = 20.0

6
Tetrahedron
ACCEPTED MANUSCRIPT
Hz, 1H, CH2), 1.95 (m, 1H, CH2), 1.81 (m, 2H, CH2), 1.68 (m,
Supplementary data related to this article can be found at
1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ = 166.8
(C=O), 144.6, 118.8, 134.7, 132.9, 130.3, 129.0, 128.2, 126.0
(Ph/=CH), 68.3(OCH), 28.6, 25.1, 19.1 (CH2).
References and notes
1
2
Otera, J.; Esterification: Methods, Reactions, and Applications
Wiley-VCH, Weinheim, 2003.
Selected reviews see:
,
,
1
Table 3, 3oa: H NMR (600 MHz, CDCl3, 298 K): δ = 7.56
(m, 1H, CHFu), 7.16 (m, 1H, CHFu), 6.49 (m, 1H, CHFu), 6.01 (m,
1H, =CH), 5.80 (m, 1H, =CH), 5.49 (m, 1H, OCH), 2.13 (dm,
(a) Tang, S.; Yuan, J.; Liu, C.; Lei, A. W. Dalton Trans
43, 13460-13470;
. 2014
1JHH = 18.1 Hz, 1H, CH2), 2.02 (dm, JHH = 18.1 Hz, 1H, CH2),
1
(b) Ekoue-Kovi, K.; Wolf, C.; Chem. Eur. J. 2008, 14, 6302-
6315;
Recent articles see:
(c) Lu, L. J.; Shi, R. Y.; Liu, L. Y.; Yan, J. W.; Lu, F. L.; Lei,
A. W. Chem. Eur. J. 2016, 22, 14484-14488;
(d) Guo, Y. F.; Xu, B. H.; Li, T.; Wang, L.; Zhang, S. J. Org.
Chem. Front. 2016, 3, 47-52;
(e) Whittaker, A. M.; Dong, V. M. Angew. Chem., Int. Ed.
2015, 54, 1312-1315;
(f) Gowrisankar, S.; Neumann, H.; Beller, M. Angew. Chem.,
Int. Ed. 2011, 50, 5139-5143.
(a) Wang, C. Y.; Song, R. J.; Wei, W. T.; Fan, J. H.; Li, J. H.
Chem. Commun. 2015, 51, 2361-2363;
(b) Zhou, J. D.; Jin, C.; Li, X. H.; Su, W. K. RSC Adv. 2015, 5,
7232-7236;
(c) Tran, B. L.; Driess, M.; Hartwig, J. F. J. Am. Chem. Soc.
2014, 136, 17292-17301;
1.96 (m, 1H, CH2), 1.86 (m, 1H, CH2), 1.81 (m, 1H, CH2), 1.69
(m, 1H, CH2). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ =
158.7 (C=O), 146.3 (Fu/=CH), 145.2 (i-Fu), 133.3, 125.5, 117.8,
111.9 (Fu/=CH), 69.0 (OCH), 28.5, 25.0, 19.0 (CH2).
Table 3, 3pa: 1H NMR (600 MHz, CDCl3, 298 K): δ = 8.0 (s,
1H, CHFu), 7.41 (s, 1H, CHFu), 6.74 (s, 1H, CHFu), 5.98 (m, 1H,
1
=CH), 5.78 (m, 1H, =CH), 5.44 (s, 1H, OCH), 2.12 (dm, JHH
=
17.9 Hz, 1H, CH2), 2.02 (dm, 1JHH = 17.9 Hz, 1H, CH2), 1.94 (m,
1H, CH2), 1.81 (m, 2H, CH2), 1.68 (m, 1H, CH2). 13C{1H} NMR
(151 MHz, CDCl3, 298 K): δ = 163.0 (C=O), 147.8, 143.7, 132.9,
125.9 (Fu/=CH), 120.0 (i-Fu), 110.0 (Fu/=CH), 68.4 (OCH), 28.5,
25.0, 19.1 (CH2).
3
1
Table 3, 3qa: H NMR (600 MHz, CDCl3, 298 K): δ = 7.79
(dd, 3JHH = 3.6 Hz, 3JHH= 1.2 Hz, 1H, CHThio), 7.53 (dd, 3JHH = 4.8
(d) Rout, S. K.; Guin, S.; Ali, W.; Gogoi, A.; Patel, B. K. Org.
Lett. 2014, 16, 3086-3089;
(e) García-Cabeza,A. L.; Marín-Barrios, R.; Moreno-Dorado,F.
J.; Ortega, M. J.; Massanet, G. M.; Guerra, F. M. Org. Lett.
2014, 16, 1598-1601;
Hz, JHH= 1.2 Hz, 1H, CHThio), 7.06 (dd, JHH= 4.8 Hz, JHH= 3.6
3
3
3
Hz, 1H, CHThio), 5.99 (m, 1H, =CH), 5.82 (m, 1H, =CH), 5.47 (m,
1H, OCH), 2.13 (dm, JHH = 17.8 Hz, 1H, CH2), 2.02 (dm, 1JHH
=
1
(f) Zhao, J. C.; Fang, H.; Han, J. L.; Pan, Y. Org. Lett. 2014
16, 2530-2533;
(g) Rout, S. K;. Guin, S.; Ghara, K. K.; Banerjee, A.; Patel, B.
K. Org. Lett. 2012, 14, 3982-3985.
(a) Liu, H. Q.; Shi, G. F.; Pan, S. L.; Jiang, Y. Y., Zhang, Y. H.
Org. Lett. 2013, 15, 4098-4101;
(b) Zhao, J. C.; Fang, H.; Zhou, W.; Han, J.; Pan, Y. J. Org.
Chem. 2014, 79, 3847-3855.
(a) Majji, G.; Guin, S.; Rout, S. K.; Behera, A. B.; Patel, K.
Chem. Commun. 2014, 50, 12193-12196;
(b) Majji, G.; Guin, S.; Gogoi, A.; Rout, S. K. Patel, B. K.
Chem. Commun. 2013, 49, 3031-3033;
(c) Huang, J.; Li, L. T.; Li, H. Y.; Husan, E.; Wang, P.; Wang,
B. Chem. Commun. 2012, 48, 10204-10206;
(d) Wei, W.; Zhang, C.; Xu, Y.; Wan, X. B.; Chem. Commun.
2011, 47, 10827-10829;
(e) Shi, E.; Shao, Y.; Chen, S. L.; Hu, H. Y.; Liu, Z. J.; Zhang,
J.; Wan, X. B. Org. Lett. 2012, 14, 3384-3387.
Selected reviews see:
(a) Gensch, T.; Hopkinson, M. N.; Glorius, F.; Wencel-Delord,
J. Chem. Soc. Rev. 2016, 45, 2900-2936;
(b) Girard, S. A.; Knauber, T.; Li, C. J. Angew. Chem., Int. Ed.
2014, 53, 74-100;
(c) White, M. C. Science. 2012, 335, 807-809;
(d) Zhang, S. Y.; Zhang, F. M.; Tu, Y. Q. Chem. Soc. Rev.
2011, 40, 1937-1949;
,
17.8 Hz, 1H, CH2), 1.95 (m, 1H, CH2), 1.87 (m, 1H, CH2), 1.81
(m, 1H, CH2), 1.68 (m, 1H, CH2). 13C{1H} NMR (151 MHz,
CDCl3, 298 K): δ = 162.1 (C=O), 134.6 (i-Thio), 133.3, 133.1,
132.3, 127.8, 125.6 (Thio/=CH), 69.1 (OCH), 28.5, 25.0, 19.0
(CH2).
Scheme 4, 3ah: 1H NMR (600 MHz, CDCl3, 298 K): δ = 8.06
(m, 2H, o-Ph), 7.57 (m, 1H, p-Ph), 7.45 (m, 2H, m-Ph), 6.81 (m,
1H, =CH), 6.19 (m, 1H, =CH), 5.50 (m, 1H, OCH), 2.11 (m, 1H,
CH2), 1.96 (m, 3H, CH3=CH), 1.92 (m, 1H, CH2), 1,73 (m, 1H,
CH2), 1.58 (s, 3H, CH3), 1.54 (m, 1H, CH2), 1.11 (s, 3H, CH3),
1.08 (s, 3H, CH3). 13C{1H} NMR (151 MHz, CDCl3, 298 K): δ =
200.5 (C=O), 166.5 (C=O), 146.7, 146.0, 134.0, 133.1, 130.6,
129.8, 128.5, 128.0 (Ph/=CH/=C), 71.8 (OCH), 35.2 (Cq), 34.1,
28.8 (CH2) 27.8, 25.6, 18.7, 18.0 (CH3).
4
5
1
6
Scheme 4, β-damascenon: H NMR (600 MHz, CDCl3, 298
K): 6.81 (dm, 3JHH = 15.7 Hz, 1H, =CHMe) 6.17 (dq, 3JHH = 15.7
4
3
Hz, JHH = 1.6 Hz, 1 H, =CHC=O), 5.83 (dm, JHH = 9.6 Hz, 1 H,
=CHCq), 5.78 (dm, 3JHH = 9.6 Hz, 1 H, =CHCH2), 2.09 (dd, 3JHH
4.2 Hz, 3JHH = 1.6 Hz, 2H, CH2), 1.92 (ddm, 3JHH = 6.9 Hz, 4JHH
=
=
1.6 Hz, 3 H, CH3CH=CH), 1.62 (s, 3 H, CH3C=C), 1.02 (s, 6 H,
2×CH3). 13C{1H} NMR (151 MHz, CDCl3, 298 K): 201.2
(C=O), 146.5 (CHMe), 139.4 (=CqC=O), 134.7 (=CHC=O), 128.2
(=CqMe), 128.1 (=CHCH2), 127.4 (=CHCq), 39.5 (CH2), 33.9
(CMe2), 26.4 (2×CH3), 19.6 (CH3Cq), 18.6 (CH3=CH).
(e) Liu, C.; Zhang, H.; Shi, W.; Lei, A. W. Chem. Rev. 2011
,
111, 1780-1824.
(a) Bras, J. L.; Muzart, J. Tetrahedron: Asymmetry. 2003, 14,
1911-1915;
7
(b) Marín-Barrios, R.; Guerra, F. M.; García-Cabeza, A. L.;
Moreno-Dorado, F. J.; Massanet, G. M. Tetrahedron. 2012, 68
1105-1108;
,
Acknowledgments
(c) Alvarez, L. X.; Christ, M. L.; Sorokin, A. B. Appl. Catal. A:
General. 2007, 325, 303-308;
(d) Tan, Q. T.; Hayashi, M. Adv. Synth. Catal. 2008, 350,
Financial support from the National Key Projects for
Fundamental Research and Development of China
(2016YFB0601303), National Natural Science Foundation of
China (No. 21476240), Key Program of National Natural Science
Foundation of China (No. 91434203), Instrument Developing
Project of the Chinese Acad-emy of Sciences (No. YZ201521)
and CAS (Chinese Academy of Sciences) 100-Talent Program
(2014) is greatly acknowledged.
2639-2644.
8
9
Mo, H. J.; Chen, D. B.; Xu, L. Z.; Chen, D.; Pan, F. Y.; Yang, J.
G. Synthesis. 2015, 47, 209-215.
(a) Kharasch, M. S.; Sosnovsky, G. J. Am. Chem. Soc. 1959
,
81, 5819-5824;
(b) Kharasch, M. S.; Sosnovsky, G. J. Am. Chem. Soc. 1958
,
80, 756.
10 (a) Guo, Y. F.; Ren, T. L.; Xu, B. H.; Wang, Y. F.; Zhang, S. J.
Asian J. Org. Chem. 2016, 5, 568-574;
Acknowledgments Appendix A. Supplementary data
(b) Spier, E.; Neuenschwander, U.; Hermans, I. Angew. Chem.,
Int. Ed. 2013, 52, 1581-1585;

7
(c) Yao, H.; Yamamoto, K. Chem. Asian J. 2012, 7, 1542-
1545;
ACCEPTED MANUSCRIPT
(d) Kim, J. Y.; Cho, S. H.; Joseph, J.; Chang, S. Angew. Chem.,
Int. Ed. 2010, 49, 9899-9903;
(e) Richardson, W. H. J. Org. Chem. 1965, 30, 2804-2808.
11 (a) Onopchenko, A.; Schulz, J. G. D. J. Org. Chem. 1973, 38,
3729-3733;
(b) Lande, S. S.; Kochi, J. K. J. Am. Chem. Soc. 1968, 90,
5196-5207.
12 (a) Wu, X. S.; Yang, K.; Zhao, Y.; Sun, H.; Li, G. G.; Ge, H.
B. Nat. Commun. 2015, 51, 7462-7471;
(b) Zhao, D.; Kim, J. H.; Stegemann, L.; Strassert, C. A.;
Glorius, F. Angew. Chem., Int. Ed. 2015, 54, 4508-4511;
(c) Li, J.; Ackermann, L. Angew. Chem., Int. Ed. 2015, 54,
8551-8554;
(d) Grigorjeva, L.; Daugulis, O. Angew. Chem., Int. Ed. 2014
,
53, 10209-10212;
(e) Shigehisa, H.; Aoki, T.; Yamaguchi, S.; Shimizu, N.;
Hiroya, K. J. Am. Chem. Soc. 2013, 135, 10306-10309.
13 Campagnole, M.; Delmond, B. Synth. Commun. 2007, 37,
1077-1090.
14 (a) Cheng, Y. Y.; Ren, T. L.; Xu, B. H.; Tao, H. S.; Zhang, S.
J. Flavour Fragr. J. 2016, 31, 420-428;
(b) Azzari, E.; Faggi, C.; Gelsomini, N.; Taddei. M. J. Org.
Chem. 1990, 55, 1106-1108.