Direct preparation of benzylic manganese reagents from benzyl halides, sulfonates, and phosphates and their reactions: Applications in organic synthesis

Article abstract of DOI:10.1016/S0022-328X(03)00500-X

The use of highly active manganese (Mn)*, prepared by the Rieke method, was investigated for the direct preparation of benzylic manganese reagents. The oxidative addition of the highly active manganese to benzylic halides was easily completed under mild conditions. Moreover, benzylic manganese sulfonates and phosphates were prepared by direct oxidative addition of Mn* to the carbon-oxygen bonds of benzylic sulfonates and phosphates. The resulting benzylic manganese reagents were found to undergo cross-coupling reactions with a variety of electrophiles. Most of these reactions were carried out in the absence of any transition metal catalyst under mild conditions. In addition, the use of highly active manganese was also studied for preparation of homo-coupled products of functionalized benzyl halides without transition metal catalysts. These useful approaches provided not only a facile synthetic route to the preparation of resoricinolic lipids but a facile synthesis of functionalized 4-benzylpyridines by regioselective and chemo selective γ-addition of benzylic group to N-alkoxycarbonylpyridinum salts.

Full text of DOI:10.1016/S0022-328X(03)00500-X

Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
www.elsevier.com/locate/jorganchem
Direct preparation of benzylic manganese reagents from benzyl
halides, sulfonates, and phosphates and their reactions: applications
in organic synthesis
YoungSung Suh, Jun-sik Lee, Seoung-Hoi Kim, Reuben D. Rieke *
Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
Received 17 April 2003; received in revised form 20 May 2003; accepted 23 May 2003
Dedicated to Professor Ernst Otto Fischer the pioneer of organometallic chemistry on the occasion of the 85th birthday
Abstract
The use of highly active manganese (Mn)*, prepared by the Rieke method, was investigated for the direct preparation of benzylic
manganese reagents. The oxidative addition of the highly active manganese to benzylic halides was easily completed under mild
conditions. Moreover, benzylic manganese sulfonates and phosphates were prepared by direct oxidative addition of Mn* to the
carbonꢀoxygen bonds of benzylic sulfonates and phosphates. The resulting benzylic manganese reagents were found to undergo
/
cross-coupling reactions with a variety of electrophiles. Most of these reactions were carried out in the absence of any transition
metal catalyst under mild conditions. In addition, the use of highly active manganese was also studied for preparation of homo-
coupled products of functionalized benzyl halides without transition metal catalysts. These useful approaches provided not only a
facile synthetic route to the preparation of resoricinolic lipids but a facile synthesis of functionalized 4-benzylpyridines by
regioselective and chemo selective g-addition of benzylic group to N-alkoxycarbonylpyridinum salts.
# 2003 Elsevier B.V. All rights reserved.
Keywords: Manganese; Benzyl manganese reagents; Palladium; Cross-coupling; Homo-coupling
1. Introduction
coupling products even at low temperature [1]. Similar
problems are frequently observed in the preparation of
benzylic Grignard reagents. The magnesium anthracene
complex involving an electron transfer mechanism has
been extensively used to alleviate these problems [3]. In
some cases, more efficient direct synthetic methods
utilizing the oxidative addition of a metal to the
corresponding benzyl halides have been developed
including activated zinc [4] and cadmium [5a]. However,
a copper catalyst was needed to complete the cross-
coupling reaction of benzylic zinc halides with electro-
philes. Recently, an interesting new synthetic procedure
for preparing benzylic zinc reagent has been reported
using triorganozincate and 4-iodobenzyl mesylates [6].
This system appears very useful for the preparation of 4-
alkyl substituted benzylic zinc reagents.
Benzylic organometallic reagents have been playing
an important role in organic synthesis, especially in
homologation of organometallics. In spite of their
significance, developments of synthetic methods for
the preparation of benzylic metal reagents have been
limited.
One of the earliest studies of benzylic metal chemistry
concerns benzylic lithium reagents. Most benzylic
lithium reagents have been prepared via bond cleavage
reactions [1] and/or transmetalation reactions [2]. How-
ever, in general, these methods are often accompanied
by the formation of complex mixtures and homo-
* Corresponding author. Tel.: ꢁ
9402.
E-mail address: rrieke1@unl.edu (R.D. Rieke).
/
1-402-472-3501; fax: ꢁ1-402-472-
/
Even though some practical synthetic pathways have
been developed using active zinc with benzylic halides
0022-328X/03/$ - see front matter # 2003 Elsevier B.V. All rights reserved.
doi:10.1016/S0022-328X(03)00500-X

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
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21
[5b,5c], more facile approaches would be of value to
Table 1
Coupling reaction with acid chlorides
organic synthesis. We now describe an alternative
synthetic route for the direct formation of nonfunctio-
nalized and functionalized benzylic manganese halides
from the oxidative addition reaction of highly active
manganese to benzylic halides [7]. More significantly,
benzylic manganese sulfonates and phosphates were
prepared by the reaction of Mn* (prepared by the Rieke
Method) with the corresponding benzylic sulfonates and
phosphates. The resulting benzylic manganese reagents
were found to undergo a variety of cross-coupling
reactions. It was also found that homo-coupled pro-
ducts of functionalized benzyl halides could be readily
prepared depending on reaction conditions.
2. Results and discussion
2.1. Preparation and coupling reactions of benzylic
manganese halides
Highly activated manganese metal (Mn*) can be
prepared via the lithiumꢀnaphthalene reduction method
/
in freshly distilled THF at room temperature [8].
Treatment of the highly active manganese (Mn*) with
benzyl halides (Br and Cl) gave high yields of the
corresponding benzylic manganese halides. The result-
ing benzylic manganese halides reacted readily with a
variety of electrophiles to give the corresponding
products. It is worthy to note that most of these
coupling reactions were carried out in absence of a
transition metal catalyst. The environmental advantage
of carrying out these reactions without a transition
metal is significant.
While the oxidative addition of Mn* prepared from
manganese bromide and chloride to benzyl halides were
completed at room temperature in 20 min in THF
(Scheme 1), small amounts (3ꢀ9%) of homo-coupling
/
products of benzyl halides were observed. However, use
of manganese iodide [9] to prepare active Mn* alleviated
the problem. Less than 1% of homo-coupling products
were formed in these cases.
The benzylic manganese halides were reacted with
acid chlorides to obtain the cross-coupling products and
the results are summarized in Table 1. The cross-
coupling reactions with acid chlorides were carried out
at room temperature and were completed in 30 min in
THF in the absence of any transition metal catalyst
Scheme 1.

22
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
(except entry 13, Table 1). An excess of acid chloride
was employed in these reactions to avoid the addition
reaction of the remaining benzylic manganese halides to
ketones, formed. Both aryl (I, II) and alkyl (III, IV) acid
chlorides gave excellent yields (Table 1). Some functio-
Table 2
Cross-coupling reaction of benzylic manganese bromide
nalized benzylic manganese halides (entries 4ꢀ9 and 13,
/
Table 1) have been prepared as well as non-functiona-
lized ones (entries 1 and 2, Table 1). Of special interest is
entry 8 in Table 1. Preparing oragnometallic reagents
with compounds containing a trifluoromethyl group can
be problematic. However, 1g was readily converted to
the corresponding organomanganese reagent, and sub-
sequent cross-coupling reaction proceeded in excellent
yield. The oxidative addition tolerates an electron-with-
drawing group such as a carbomethoxy group (entry 13,
Table 1). In contrast to the rest of the entries in Table 1,
the manganese derivative of 1j does not undergo cross-
coupling reaction in the absence of catalyst. However,
product 2l readily formed in the presence of a catalytic
amount of CuI. Interestingly, treatment of Mn* with
a,a?-dichloro-m-xylene (1i) and the consecutive coupling
reaction with benzoyl chloride gave a symmetrical biaryl
compounds 2i in 79% yield (entry 10, Table 1).
The benzylic manganese halides were also found to
react with other electrophiles such as aldehydes, ke-
tones, and di-tert-butylazodicarboxylate (DBAD). The
results are shown in Table 2. Addition to aldehydes
(entries 1ꢀ/4 and 7, Table 2) gave the corresponding
secondary alcohols in good yields (78ꢀ/93%). The
reaction tolerated halides or a nitrile group (entry 2 or
3, Table 2) in the aldehyde but not a nitro group. The
addition to an alkyl ketone yielded the corresponding
tertiary alcohol 3e in good yield (entry 5, Table 2). But
coupling with acetophenone afforded the tertiary alco-
hol in low yield (entry 6, Table 2). DBAD was also
employed as an electrophile, and the corresponding
coupling product 3i was obtained in excellent yield
(80%). It should be noted that the coupling reactions
described above have been readily accomplished in the
absence of any catalyst under mild conditions.
nalized benzylic sulfonates and phosphates later. Benzyl
sulfonates and phosphates can be easily prepared from
the corresponding alcohols using standard literature
procedures [11,12]. Simply stirring the mixture of an
alcohol and methane sulfonyl chloride or p-toluene
sulfonyl chloride in methylene chloride at room tem-
perature in the presence of triethylamine followed by a
simple workup procedure yielded the sulfonates in over
80% isolated yields. The synthesis of organophosphates
was also easily conducted using the corresponding
alcohol and commercially available diethyl chloropho-
sphate in presence of triethylamine in THF or sodium
hydride and diethyl cholorophosphate in THF followed
by purification by column chromatography (65% yield).
A variety of functionalized benzyl sulfonates and
phosphates were prepared by this approach and were
used for the preparation of functionalized benzylic
manganese reagents. This route provides a significant
new approach to benzylic reagents and obviates the need
for the corresponding halide, which in many cases is
problematic.
2.2. Preparation and coupling reactions of benzylic
manganese sulfonates and phosphates
In 1992, Yus et al. reported that allyic and benzylic
mesylates reacted with lithium naphthalenide to give the
corresponding organolithium reagents giving cross-cou-
pling products upon treatment with electrophiles
[10,10a].
Considering the high reactivity of the active manga-
nese (Mn*) metal prepared by the Rieke method and the
exceptional tolerance to a wide range of functionality in
the organic moiety, we explored the possibility of the
direct oxidative addition to a variety of carbonꢀoxygen
/
bonds. Our first approach employed benzyl sulfonates.
This was expanded to functionalized and non-functio-
Importantly, this study demonstrates that highly
active manganese readily undergoes oxidative addition

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
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23
to carbonꢀ
/
oxygen bonds of benzyl sulfonates and
Table 3
Cross-coupling of benzylic and functionalized benzylic manganese
sulfonates
phosphates. Also, the subsequent cross-coupling reac-
tions with a variety of electrophiles can be easily carried
out. The synthetic advantages of the approach are
apparent considering few reports [13] exist of the
oxidative addition of main group or even transition
metals to carbonꢀoxygen bonds. Of particular interest is
/
the availability of tosylates, mesylates and phosphates as
precursors to organomanganese reagents (Scheme 2).
Table 3 contains the summarized results of coupling
reaction of benzylic manganese sulfonates. The oxida-
tive addition of active manganese to benzyl sulfonates
was easily completed at room temperature in only 30
min. According to GC analysis, a small amount (B8%)
/
of homo-coupled product, bibenzyl, was formed during
the reaction. The resulting benzylic manganese sulfo-
nates were cross-coupled with several electrophiles. The
coupling reactions were completed under mild condi-
tions and significantly in the absence of any transition
metal catalyst.
Functionalized benzylic mesylates containing a halo-
gen atom were also investigated. Reactions of the
halogenated benzyl manganese mesylates with acid
chlorides, aldehydes, and ketones, yielded the corre-
sponding ketone, secondary alcohol, and tertiary alco-
hol in good to excellent isolate yields as shown in Table
3. As mentioned earlier, it is of interest that the mesylate
containing trifluoromethyl group has been successfully
employed for the preparation of benzylic manganese
mesylate, and the subsequent coupling reaction pro-
ceeded in good yield (89%).
As shown in Table 4, the oxidative addition to alkyl
tosylates and coupling reactions of organomanganese
tosylates were also investigated. The oxidative addition
was easily completed by simple treatment of Mn* with
the alkyl tosylates at room temperature in THF.
Unfortunately, no oxidative addition was found to
occur with phenyl tosylate even at refluxing tempera-
tures (entry 9, Table 4). The formation of organoman-
ganese tosylates was also confirmed by the subsequent
cross-coupling reaction with different electrophiles. The
tosylates listed in Table 4 reacted with benzoyl chloride
to afford the corresponding ketones in moderate to
excellent yields (44ꢀ86%). Once again, the coupling
/
reaction was carried out at room temperature in THF in
the absence of any transition metal catalyst. In contrast
to all the primary tosylates, a low yield (17%) was
obtained from a secondary tosylate. This may due to the
steric hindrance and/or easy elimination of organoman-
ganese tosylate yielding alkenes. Cross-coupling reac-
tion with benzaldehyde also gave the corresponding
alcohols in moderate yields (36ꢀ64%).
/
Non-functionalized and functionalized benzyl phos-
phates were treated with Mn* under the same conditions
used for benzyl sulfonates. However, in the case of
Scheme 2.

24
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
Table 4
Preparation of organomanganese tosylates and their coupling reaction
benzyl phosphates, a longer reaction time was required
to complete the oxidative addition compared to the
cases of benzyl mesylate and tosylate. The oxidative
ketones. The results are summarized in Table 6. Addi-
tion to aldehydes gave the corresponding secondary
alcohols in moderate yield (38ꢀ76%). However, the
/
addition of Mn* to the CÃ/O bond of the phosphate was
addition reaction to acetophenone afforded the tertiary
alcohol in low yield (19%). The reaction tolerated a
nitrile group in the aldehyde (entry 8, Table 6), but not a
nitro group. When p-cyanobenzyl diethyl phosphate
was treated with Mn*, only the homo-coupled product
was observed under a wide range of reaction conditions.
To expand the range of phosphates for preparation of
organomanganese phosphates, alkyl-, phenyl-, and allyl
diethyl-phosphates were attempted. Unfortunately, the
oxidative addition of active manganese (Mn*) to these
phosphates and the subsequent coupling reactions with
electrophiles failed to give the corresponding cross-
coupled products.
completed after being stirred at room temperature
overnight (8 h). According to GC and TLC analysis, a
trace amount of homo-coupling product was observed.
The subsequent coupling reactions of the resulting
benzylic manganese phosphates with acid chlorides,
benzaldehydes, and ketones, gave the corresponding
products in moderate to good yields at room tempera-
ture in dry THF in the absence of any transition metal
catalyst. To facilitate the oxidative addition to the
organophosphates, use of a sonicator or increase of
reaction temperature was examined. But, this resulted in
the formation of un-expected side products and was not
continued. The results of the coupling reactions of
nonfunctionalized as well as functionalized benzylic
manganese phosphates with acid chlorides are summar-
ized in Table 5. These results indicate that a wide range
of functional groups can be tolerated under these
conditions. The ethyl groups in the starting phosphate
were replaced with phenyl groups with little or no effect
on the overall reaction (entries 2 and 3, Table 5). In
contrast to all the rest of the entries in Table 5, the
manganese derivatives of 8j do not undergo cross-
coupling without Cu catalyst. In the presence of CuI,
product 2l was obtained in 39% yield.
Overall, the isolated yields obtained from using benzyl
sulfonates and phosphates were lower than those from
using benzyl halides. At this time, we do not understand
fully why the manganese halides give better yields than
the manganese sulfonates or phosphates. However, this
unusual oxidative addition to CÃ/O bond of benzyl
sulfonates, and phosphates under mild condition and
the resulting organomanganese reagents provide a new
synthetic route to benzylic manganese reagents. More-
over, to our knowledge, these are the first examples of
organomanganese sulfonates and phosphates prepared
via direct oxidative addition of manganese metal or by
any methasis approach.
The benzylic manganese phosphates were also found
to react with other electrophiles including aldehydes and

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
25
Table 5
Coupling reactions of benzylic manganese phosphates with acid chlorides

26
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
Table 6
Addition reactions of benzylic manganese phosphates
Scheme 4.
Best results were obtained when the active manganese
was added to the neat benzyl bromide. The reaction was
completed within 10 min at room temperature without a
catalyst [14]. Several other benzyl halides produced good
to excellent yields of homo-coupling products, which
showed a wide tolerance of functional groups such as
nitrile, ester, nitro, chloro, bromo, methoxy, and methyl
group (Table 8).
Our method is more efficient compared to the
previous attempts to prepare functionalized bibenzyl
compounds [15] in terms of milderness and speed of the
reaction. More significantly, no transition metal catalyst
(Pd or Ni) was required for completion of the reaction
nor was a solvent required.
2.4. Palladium-catalyzed cross-coupling reaction of
benzylic manganese reagents
Cross-coupling reactions of alkyl organometallic
compounds with alkyl or aryl halides are difficult to
perform because of the slow oxidative addition of alkyl
halides to the palladium and slow reductive elimination
2.3. Homo-coupling reaction of functionalized benzylic
manganese reagents
of dialkyl or alkylꢀaryl products. Only limited examples
/
Table 7
Homo-coupling reactions of benzyl bromides at different reaction
conditions
We examined the homo-coupling of benzyl halides
under the influence of active manganese in a wide
variety conditions.
As shown in Table 7, one equivalent of active
manganese and two equivalents of benzyl bromide
produced 47% of homo-coupling products. But the
homo-coupling yield was decreased to 27% by using
one equivalent of benzyl bromide.
Scheme 3.

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
27
Table 8
Homo-coupling reactions of benzyl halides
reaction times and in some cases they did not tolerate
functional groups.
Benzylic manganese halides and phosphates were also
found to undergo palladium-catalyzed cross-coupling
a
Entry
R1
R2
X
Product
Yield
reactions with aryl iodides (sp3ꢀsp2 coupling). As
Shown in Schemes 3 and 4 (Table 9), the corresponding
cross-coupling compounds were achieved in moderate to
/
1
4-CN
3-CN
H
Br 11a
Br 11b
Br 11c
Br 11d
Br 11e
Br 11f
Br 11g
Cl 11h
Cl 11i
Cl 11j
Cl 11k
82
90
2
H
3
2-CN
H
H
84
85
4
CH3
H
good yields using
5
mol.% palladium catalyst
[Pd(PPh3)4] in THF within 2 h at room temperature.
5
4-CO2Me
4-NO2
4-Br
80
6
H
34 b
60 c
65 c
77 c
70 c
59 c
7
H
8
4-Cl
H
2.5. Applications
9
2,6-diCl
3,5-diOMe
2-CH3
H
10
11
H
H
As described above, the benzylic manganese reagents
have been found to undergo reactions with aldehydes
and acid chlorides under mild conditions. Interestingly,
this approach can be easily applied to the preparation of
resorcinolic lipid precursors. Resorcinolic lipids of the
general type A are mainly isolated from plants as
presented below. In general, 5-n-alkylresorcinols have
shown a variety of biological activities including anti-
microbial, antiparasitic, cytotoxic activity, growth reg-
ulator, and DNA cleaving properties [18]. As shown in
a
Isolated yields.
0.64 equivalents of ArCH2X was used.
Yields obtained after recrystallization over hexanes.
b
c
are reported for the cross-coupling of the benzyl
Scheme 5, the key step in this synthesis is the CÃ
/
C bond
formation. The CÃC bond can be obtained by the
/
reaction of an arylmetallic reagents with alkyl substrates
(or vice versa) followed by the reduction of functional
groups to give rise to the alkyl chains.
Scheme 5.
To this end, a few synthetic methods have been
reported for the preparation of 5-n-alkylresorcinols.
These methods include the use of 3,5-dimethoxybenzal-
dehyde [19], 3,5-dimethoxy-benzylic alcohol [20], and
3,5-dimethoxyphenol [21]. Until recently, because of the
difficulty of the preparation of benzylic metal reagents
[22], only one resorcinol, olivetol, has been prepared
using 3,5-dimethoxybenzylic magnesium chloride [23].
As already reported, cross-coupling reactions of
benzylic manganese chloride with aldehydes and acid
chlorides readily afforded the corresponding coupling
products. Therefore, we can apply this approach to the
preparation of 5-n-alkylresorcinols and/or their precur-
sors.
Scheme 6.
organometallic compounds with aryl halides. Betzemeier
and Knochel [4a] reported the palladium catalyzed
cross-coupling of benzylzinc bromides with aryl iodides
in perfluorinated solvents and Park et al. [16] prepared
diarylmethanes from benzylmagnesium chlorides and
aryl bromides with nickel catalyst. Yoshida et al. [17]
prepared functionalized diarylmethanes from cross-cou-
pling reactions of (2-pyridyl)silylmethylstannanes and
aryl iodides with a palladium catalyst and additive. The
above-mentioned methods required additives and long
Cross-coupling reactions of 3,5-dimethoxybenzylic
manganese chloride with alkyl aldehydes and acid
chlorides were carried out at room temperature in
absence of any catalyst to give the corresponding
Table 9
Palladium catalyzed cross-coupling reactions of benzyl manganese halides and phosphate with aryl iodides
a
Entry
R1
R2
X
Product
Yield
1
2
3
4
5
H
4-Br
4-CO2Et
4-CO2Et
3-CN
Br
Br
12a
12b
12c
12d
12d
78
56
40
64
40
3,5-diOMe
4-Cl
4-Cl
Cl
Cl
4-CO2Et
4-CO2Et
OP(O)(OEt)2
a
Isolated yields.

28
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
catalyst for the addition reaction. The intermediate, 1,4-
dihydropyridines, were found to be somewhat stable in
air at room temperature. On exposure to oxygen for
more than 8 h or to sulfur in decalin under reflux, the
intermediate compounds (19) were readily oxidized to
the corresponding 4-benzylpyridines. Therefore, our
method provides an easy access to the synthesis of
functionalized 4-benzylpyridines. More interestingly,
this approach provides a regio- and chemo-selective
synthesis of functionalized 1,4-dihydro-pyridines, which
have been shown to be biologically important sub-
stances as well as useful synthetic intermediates for
nitrogen heterocycles [29].
Scheme 7.
coupling products (13aꢀd), respectively in excellent
/
isolated yields. All of the compounds listed in Scheme
6 can be used as intermediates for the preparation of 5-
n-alkylresorcinols [24,30].
Furthermore, as shown in Scheme 7, simple coupling
reactions of 1f with aryl aldehydes yielded the coupling
products in excellent isolated yields under mild condi-
tions. It should be noted that this approach provides a
more facile route than using benzyloxytrimethylsilane
[20] in terms of the yield.
Another convenient approach to a synthesis of
functionalized 4-benzylpyridines becomes feasible be-
cause of the facile synthetic route to benzylic manganese
reagents.
A few methods have been developed for the reiose-
lective introduction of a carbon substituent in the four-
position of a pyridine ring: organocopper reagents [25],
silyl enol ethers [26], and titanium enolates [27] attack
regioselectively the g-position of N-alkyl-carbonylpyr-
idium salts to give 4-substituted 1,4-dihydropyridines.
More recently, Yamaguchi et al. [28] reported that a
very expensive benzyltin reagent could be added to the
four position of a pyridine ring. And also, use of mixed
copper, zinc benzylic organometallics for regio- and
chemoselective addition to functionalized pyridium salts
has been reported [4e].
2.6. Limitations of this approach
A number of different types of benzyl substrates,
diethyl benzylphosphonate, benzyl methyl sulfide, ben-
zyl phenyl sulfide, benzyl benzoate, benzyl phenyl ether,
and benzyloxytrimethylsilane were also reacted with
Mn*. Unfortunately, according to TLC and/or gas
chromatography analyses, no oxidative addition oc-
curred with these substrates.
As shown in previous tables containing cross-coupling
products, a number of different types of electrophiles
were used to complete the cross-coupling reaction of
benzylic manganese reagents prepared via direct oxida-
tive addition of Mn* to the corresponding benzylic
halides, sulfonates, and phosphates. Apparently, func-
tional group tolerance is a big advantage of this system.
However, no coupling products were obtained from the
coupling reactions with the following substarates: p-
nitrobenzaldehyde, epoxides, ester and alkyl cyanides.
In view of the feasibility and the high reactivity of
benzyl manganese reagents, we examined the reactivity
of benzyl nucleophiles towards pyridium salts. Interest-
ingly, it was found that the reaction of N-ethoxycarbo-
nylpyridium chloride, prepared in situ from ethyl
chloroformate and pyridine, with benzyl as well as
substituted benzyl organometallics proceeded smoothly
with high g-selectivity at room temperature to obtain
regioselectively 4-benzylpyridines after oxidation in
good yield (Scheme 8).
3. Experimental
3.1. General methods
1H-NMR (300 MHz) spectra were recorded in CDCl3
solution. All chemical shifts are reported in parts per
million (d). Fully decoupled 13C-NMR (75 MHz)
spectra were recorded in CDCl3 solution. Tetramethyl-
silane was used as a reference in H-NMR experiments
and the center peak of CDCl3 (77.7 ppm) was used as
the internal reference in 13C-NMR experiments.
1
However, it should be noted that in the absence of a
Cu catalyst, the addition reaction of benzyl manganese
reagents did not take place. CuI (5 mol.%) was used as a
All manipulations were carried out under argon on a
dual manifold of vacuum/argon system. The Linweld
prepurified grade argon was further purified by passage
over a BASF R3-11 catalyst column at 150 8C, a
phosphorus pentoxide column, and a column of gran-
ular potassium hydroxide. Lithium, naphthalene, and
manganese halides were weighed out and charged into
reaction flasks under argon in a Vacuum Atmospheres
Company drybox. Tetrahydrofuran was distilled imme-
diately before use from Na/K alloy under argon.
Scheme 8.

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
29
Gas chromatographic analyses were done on a
HewlettꢀPackard 6890 chromatograph using HP-5
cross-linked 5% phenyl methyl siloxane column (0.32
mmꢂ30 M). Analytical thin-layer chromatography was
performed using Merck 5735 indicating plates precoated
with silica gel 60 F254 (layer thickness 0.2 mm). The
product spots were visualized with either UV lamp or a
phosphomolybdic acid reagent (20 wt.% solution in
ethyl alcohol). Liquid chromatographic purification was
performed by flash column chromatography using glass
126.83, 128.53, 128.60, 129.41, 133.10, 134.48 136.54,
197.55 ppm.
/
/
3.3.2. Benzyl 4-bromophenyl ketone (2b)
1
White solid; m.p.: 112ꢀ
CDCl3, 25 8C): dꢃ
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
113 8C. H-NMR (300 MHz,
/
4.26 (s, 2H), 8.02ꢀ
/7.24 (m, 9H) ppm.
/45.47, 127.00,
128.33, 128.74, 129.33, 130.10, 131.92, 132.35, 134.09,
135.20, 196.54 ppm.
columns packed with Merck silica gel 60 (230ꢀ400
mesh).
/
3.3.3. 4-Bromobenzyl phenyl ketone (2c)
1
White solid; m.p.: 147ꢀ
CDCl3, 25 8C): dꢃ
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
148 8C. H-NMR (300 MHz,
/
4.25 (s, 2H), 8.02ꢀ/7.13 (m, 9H) ppm.
3.2. Preparation of highly active manganese (Mn*)
/
44.67, 120.89,
128.44, 128.68, 131.22, 131.66, 133.32, 133.39, 136.30,
196.92 ppm.
To the mixture of lithium (4.4 mmol), naphthalene
(0.4 mmol), and manganese halides (2 mmol) was added
via syringe freshly distilled THF (10 ml) at room
temperature (r.t.) and then the resulting mixture was
allowed to stir at r.t. for 1 h. The black slurry was
obtained and ready for use. (Note: the number of
millimoles of Mn* cited in this paper refers to the
theoretical amount possible based on the original
amount of anhydrous manganese halide.) No attempt
was made to determine whether the Mn*, either wet as
slurry or pre-dried, was pyrophoric. However, it should
be treated as if it is pyrophoric and kept under argon at
all times.
3.3.4. 4-Fluorobenzyl phenyl ketone (2d)
1
White solid; m.p.: 108ꢀ
CDCl3, 25 8C): dꢃ
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
110 8C. H-NMR (300 MHz,
/
4.26 (s, 2H), 8.02ꢀ
/7.00 (m, 9H) ppm.
/44.41, 115.34,
115.52, 128.45, 128.64, 130.12, 130.15, 130.96, 131.02,
132.21, 136.46, 160.88, 162.84, 197.29 ppm.
3.3.5. 2,6-Dichlorobenzyl phenyl ketone (2e)
White solid; m.p.: 70ꢀ
CDCl3, 25 8C): dꢃ4.72 (s, 2H), 8.11ꢀ
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
80 8C. 1H-NMR (300 MHz,
/
/7.20 (m, 8H) ppm.
/41.32, 127.92,
128.15, 128.69, 128.76, 132.13, 133.36, 136.11, 194.54
ppm.
3.3. Typical preparation of benzylic manganese halides
and their coupling reactions with benzoyl chlorides to give
ketones (2aꢀl)
/
3.3.6. 3,5-Dimethoxybenzyl phenyl ketone (2f)
White solid; m.p.: 60ꢀ
CDCl3, 25 8C): dꢃ3.77 (s, 6H), 4.22 (s, 2H), 8.03ꢀ
(m, 8H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
61 8C. 1H-NMR (300 MHz,
Benzyl halide (9 mmol) in THF (2 ml) was added via a
cannula to the slurry of highly active manganese (10
mmol) being stirred in THF (15 ml) at r.t. The slurry
was stirred at r.t. for 20 min. The reaction was
monitored by gas chromatography. After the comple-
tion of the oxidative addition, the mixture was cooled to
0 8C. 1,2-Dibromoethane was added to the mixture at
this temperature to react with the excess Mn*, and the
mixture was stirred for 5 min. The resulting mixture was
transferred via cannula to the benzoyl chloride solution
in THF at r.t. After being stirred for 30 min, the mixture
was quenched with 3 M HCl solution and extracted with
diethyl ether. The combined organic layers were washed
with NaHCO3, Na2S2O3, and brine, dried over anhy-
drous MgSO4, and concentrated using a rotary eva-
porator. Flash column chromatography (ethyl acetate/
hexanes) afforded the corresponding ketones.
/
/6.35
/
45.79, 55.25, 98.89, 107.46, 128.60, 133.15, 136.51,
136.67, 146.68, 160.90, 197.39 ppm. HRMS Calc. for
C16H16O3 256.1099, Found: 256.1100.
3.3.7. Phenyl 3-trifluoromethylbenzyl ketone (2g)
1
Pale yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
dꢃ
/
4.37 (s, 2H), 8.05ꢀ
7.45 (m, 9H) ppm. 13C-NMR (75
/
MHz, CDCl3, 25 8C): dꢃ/44.77, 123.73, 123.77, 123.83,
126.33, 126.38, 128.37, 128.72, 128.92, 133.09, 133.44,
135.33, 136.27, 196.56 ppm.
3.3.8. 6-Chloropiperonyl phenyl ketone (2h)
1
Pale yellow Solid; m.p.: 124ꢀ
MHz, CDCl3, 25 8C): dꢃ
8.06ꢀ
6.72 (m, 7H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ42.92, 101.72, 109.80, 110.86, 125.74, 125.97,
/
125 8C. H-NMR (300
/4.34 (s, 2H), 5.96 (s, 2H),
/
3.3.1. Benzyl phenyl ketone (2a)
/
White solid; m.p.: 55ꢀ
CDCl3, 25 8C): dꢃ4.31 (s, 2H), 8.05ꢀ
ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
56 8C. 1H-NMR (300 MHz,
7.28 (m, 10H)
45.43,
128.27, 128.63, 133.25, 136.49, 146.4, 147.39, 196.4 ppm.
HRMS Calc. for C15H11ClO3 274.0397, Found:
274.0401.
/
/
/

30
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
3.3.9. 1,2-di-(3?-Benzylmethylphenyl)ethane (2i)
3.4.2. 1-(3-Bromophenyl)-2-phenylethan-1-ol (3b)
1
1
White solid; m.p.: 131ꢀ
CDCl3, 25 8C): dꢃ2.88 (s, 4H), 4.25 (s, 2H), 8.03ꢀ
(m, 18H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
132 8C. H-NMR (300 MHz,
Pale-brown oil. H-NMR (300 MHz, CDCl3, 25 8C):
/
/
7.04
dꢃ
4.80 Hz, 1H), 4.92, 7.19ꢀ
dꢃ46.01, 74.52, 122.49, 124.49, 126.77, 128.56, 128.95,
/
2.07 (s, 1H), 2.90ꢀ
/
3.06 (m, 2H), 4.84 (dd, Jꢃ
/4.80,
/
/
7.55 (m, 9H) ppm. 13C-NMR:
37.71, 45.46, 127.03, 128.60, 129.58, 133.10, 134.48,
136.62, 142.10, 197.71 ppm. HRMS Calc. for C30H26O2
418.1933, Found: 418.1928.
/
129.45, 129.90, 130.5, 137.42, 146.04 ppm. HRMS Calc.
for C14H13O Br 276.0150; Found: 258.0051[Mꢁ
276.0150 [Mꢁ].
ꢀH2O],
/
3.3.10. 5-Chloro-1-phenyl-2-pentanone (2j)
1
Pale brown oil. H-NMR (300 MHz, CDCl3, 25 8C):
3.4.3. 1-(4?-Cyanophenyl)-2-phenylethan-1-ol (3c)
White solid; m.p.: 66ꢀ
67 8C. 1H-NMR (300 MHz,
CDCl3, 25 8C): dꢃ2.43 (s, 1H), 2.98 (m, 2H), 4.92 (dd,
Jꢃ 7.61 (m, 9H) ppm.
dꢃ
3.51 (t, Jꢃ
ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
2.08 (q, Jꢃ
/
6.60 Hz, 4H), 2.64 (t, Jꢃ
/
6.60 Hz, 2H),
7.17 (m, 5H)
27.39,
/
/
6.60 Hz, 2H), 3.69 (s, 2H), 7.33ꢀ
/
/
/
/
5.25, 5.48 Hz, 1H), 4.94, 7.13ꢀ
/
43.88, 44.13, 29.92, 126.84, 128.52, 129.17, 133.86,
206.80 ppm.
13C-NMR: 45.3, 74.35, 11.92, 118.75, 126.49, 126.81,
128.52, 129.39, 132.02, 136.81, 148.98 ppm. HRMS
Calc. for C15H13NO 223.0997; Found: 205.0889 [Mꢁ
3.3.11. Ethyl phenylacetate (2k)
1
Pale yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
ꢀH2O).
/
dꢃ
7.15 Hz, 2H) ppm. 13Cꢀ
dꢃ14.05, 41.29, 60.67, 126.90, 128.42, 129.11, 134.08,
/
1.31 (t. Jꢃ
/
7.15 Hz, 3H), 3.67 (s, 2H), 4.22 (q, Jꢃ
/
3.4.4. 1-Phenylheptan-2-ol (3d)
Pale-yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
1
/
NMR (75 MHz, CDCl3, 25 8C):
/
dꢃ
/
1.92 (t, Jꢃ
/
6.60 Hz, 3H), 1.33ꢀ1.54 (m, 8H), 1.60 (s,
/
171.42 ppm.
1H), 2.62ꢀ
/
2.87 (m, 2H), 3.82 (m, 1H), 7.22ꢀ7.35 (m,
/
5H) ppm. 13C-NMR: d 14.00, 22.59, 25.39, 31.82, 36.73,
44.00, 72.63, 126.35, 128.47, 129.38, 138.65 ppm.
3.3.12. 4-Carbomethoxybenzyl phenyl ketone (2l)
1
White solid; m.p.: 131ꢀ
MHz, CDCl3, 25 8C): dꢃ
8.03ꢀ
7.05(m. 9H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ21.05, 44.61, 121.66, 128.57, 128.63, 130.43,
/
132 93ꢀ
/
94 8C. H-NMR (300
/
2.29 (s, 3H), 4.28 (s, 2H),
3.4.5. 2-Methyl-1-phenylheptan-2-ol (3e)
1
Pale-yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
/
/
dꢃ
/
0.93 (t, Jꢃ
/
7.16 Hz, 3H), 1.16 (s, 3H), 1.29ꢀ
/
1.47 (m,
131/98, 133.22, 136.42, 149.53, 169.39, 197.26 ppm.
10H), 2.77 (dd, Jꢃ
/
33.62, 6.91 Hz, 2H), 7.2ꢀ
/
7.35 (m,
5H) ppm. 13C-NMR: d 14.03, 22.65, 23.67, 26.45, 32.36,
41.80, 47.92, 72.48, 126.35, 128.11, 130.51, 137.60 ppm.
HRMS Calc. for C14H22O 206.1671; Found: 188.1563
3.4. Alcohols from the reactions of benzylic manganese
halides with aldehydes and ketones (3aꢀi)
/
[Mꢁ
ꢀ
/
H2O], 191.1434 [Mꢁ
ꢀCH3].
/
Benzyl halide (9 mmol) in THF (2 ml) was cannulated
to the slurry of highly active manganese (10 mmol) being
stirred in THF (15 ml) at r.t. The slurry was stirred at
r.t. for 20 min. The reaction was monitored by gas
chromatography. After the completion of the oxidative
addition, the mixture was cooled to 0 8C. 1,2-Dibro-
moethane was added to the mixture at this temperature,
and the mixture was stirred for 5 min. To the resulting
mixture was added aldehydes (or ketone) at r.t. After
being stirred for 1 h, the mixture was quenched with 2 M
HCl solution and extracted with diethyl ether. The
combined organic layers were washed with NaHCO3,
Na2S2O3, and brine, dried over anhydrous MgSO4, and
concentrated using a rotary evaporator. Flash column
chromatography (ethyl acetate/hexanes) afforded the
corresponding alcohols.
3.4.6. 2,3-Diphenylpropan-2-ol (3f)
Pale-yellow solid; m.p.: 49ꢀ
50 8C. 1H-NMR (300
MHz, CDCl3, 25 8C): dꢃ1.60 (s, 3H), 1.92 (s, 1H),
/
/
3.10 (dd, Jꢃ
/
20.27, 46.73 Hz, 2H), 7.02ꢀ7.45 (m, 10H)
/
ppm. 13C-NMR: d 29.32, 50.45, 74.39, 124.93, 126.61,
128.01, 130.57, 136.70, 147.51 ppm.
3.4.7. 2-(4?-Bromophenyl)-1-phenylethan-1-ol (3g)
Pale-yellow solid; m.p.: 39ꢀ
/
40 8C. 1H-NMR (300
MHz, CDCl3, 25 8C): dꢃ2.04 (s, 1H), 2.98 (d, Jꢃ
/
/
6.44 Hz, 2H), 4.85 (t, Jꢃ
/
6.67 Hz, 1H), 7.03ꢀ7.43 (m,
/
9H) ppm. 13C-NMR: d 45.15, 75.10, 120.41, 125.84,
127.73, 128.43, 131.22, 131.38, 136.96, 143.46 ppm.
3.4.8. 2-(4?-Bromophenyl)-1-(2?-naphthyl)ethan-1-ol
(3h)
3.4.1. 1,2-Diphenylethanol (3a)
White solid; m.p.: 96ꢀ
CDCl3, 25 8C): dꢃ2.18 (d, Jꢃ
Jꢃ
/
97 8C. 1H-NMR (300 MHz,
Pale-yellow solid; m.p.: 64ꢀ
/
65 8C. 1H-NMR (300
3.06 (m,
7.39
/
/
8.58 Hz, 1H), 3.05 (d,
MHz, CDCl3, 25 8C): dꢃ2.04 (s, 1H), 3.02ꢀ
/
/
/
6.44 Hz, 2H), 5.00 (t, Jꢃ
/
6.44 Hz, 1H), 7.04ꢀ7.88
/
2H), 4.91, (dd, Jꢃ
/
5.10, 5.10 Hz, 1H), 4.92, 7.21ꢀ
/
(m, 11H) ppm. 13C-NMR: d 45.03, 75.19, 120.44,
123.92, 124.62, 125.93, 126.19, 127.66, 127.94, 128.24,
131.24, 131.41, 132.96, 133.15, 136.89, 140.83 ppm.
(m, 10H) ppm. 13C-NMR: 46.01, 75.26, 125.85, 126.54,
127.54, 128.34, 128.43, 129.46, 137.99, 143.76 ppm.

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
31
3.4.9. N-Benzylhydrozoinodicarboxylic acid di-tert-butyl
ester (3i)
3.5.5. 2-(3?-Trifluoromethylphenyl)-1-phenylethan-1-ol
(5e)
Pale-yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
1
1
Pale-yellow solid; m.p.: 102ꢀ
MHz, CDCl3, 25 8C): dꢃ
2H), 6.25 (br s, 1H), 7.27ꢀ
7.33 (m, 5H) ppm. 13C-NMR:
/
104 8C. H-NMR (300
/1.45, 1.49 (ss, 18H), 4.64 (s,
dꢃ
/
2.14 (s, 1H), 3.08 (m, 2H), 4.87, 4.89 (dd, Jꢃ
/
5.96,
7.52 (m, 9H) ppm. 13C-NMR: d
/
5.72 Hz, 1H), 7.31ꢀ
/
d 28.12, 28.20, 81.17, 127.48, 128.46, 128.60, 128.68,
159.30 ppm.
45.41, 75.05, 123.27 (q), 125.80, 126.19 (q), 127.80,
128.44, 128.62, 132.94, 139.00, 143.36 ppm. HRFAB
Calc. for C15H13F3O 266.0918, Found: [Mꢁ
/
Li]ꢁ
3.5. Typical procedure for the cross-coupling reactions of
benzyl manganese sulfonates
273.1076.
3.5.6. 2-(2?-Chloro-4?-fluorophenyl)-1-Phenylethan-1-ol
(5f)
Benzyl mesylate (9 mmol) was added via a syringe to
the slurry of active manganese (10 mmol) being stirred
in THF (10 ml) at r.t. The resulting mixture was stirred
at r.t. for 20 min. The reaction was monitored by gas
chromatography. After the completion of the oxidative
addition, the mixture was cooled to 0 8C. 1,2-Dibro-
moethane was added to the mixture at this temperature,
and the mixture was stirred for 5 min. Benzoyl chloride
was added to the resulting mixture at r.t. After being
stirred for 30 min, the mixture was quenched with 2 M
HCl solution and extracted with diethyl ether. The
combined organic layers were washed with NaHCO3,
Na2S2O3, and brine, dried over anhydrous MgSO4, and
concentrated using a rotary evaporator. Flash column
chromatography (ethyl acetate/hexanes) afforded the
corresponding ketones.
Pale-yellow solid; m.p.: 64ꢀ
MHz, CDCl3, 25 8C): dꢃ2.39 (br s, 1H), 3.03ꢀ
(m, 2H), 4.93, 4.96 (dd, Jꢃ5.25, 5.01 Hz, 1H), 6.86ꢀ
/
66 8C. 1H-NMR (300
3.18
/
/
/
/
7.36 (m, 9H) ppm. 13C-NMR: d 42.68, 73.30, 113.56,
113.83, 116.44, 116.76, 125.64, 127.64, 128.36, 131.76,
131.81, 132.69, 132.81, 134.53, 134.66, 143.62, 159.58,
162.87 ppm. HRFAB Calc. for C14H12ClFO 250.0561,
Found: [Mꢁ
Li]ꢁ 257.0729.
/
3.5.7. 2-(3?-Methoxyphenyl)-1-phenylethan-1-ol (5g)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.24 (s, 1H),
3.00, 3.03 (dd, Jꢃ3.10, 5.96 Hz, 2H), 3.78 (s, 3H), 4.88,
4.91 (dd, Jꢃ 7.39 (m, 8H)
/
/
/
5.48, 5.45 Hz, 1H), 6.75ꢀ
/
ppm. 13C-NMR: d 45.98, 54.99, 75.06, 111.98, 114.95,
121.72, 125.81, 127.45, 128.27, 129.33, 139.52, 143.70,
159.50 ppm.
3.5.1. 1-Benzylcyclohexan-1-ol (5a)
1
Pale-yellow oil. H-NMR (300 MHz, CDCl3, 25 8C):
3.5.8. Heptyl phenyl ketone (7a)
dꢃ
/
1.26 (m, 8H), 1.39 (t, 4H), 2.76 (s, 2H), 7.08ꢀ
/
7.22
(m, 5H) ppm. 13C-NMR: d 18.75, 27.87, 38.06, 46.88,
69.26, 125.78, 128.33, 139.48 ppm.
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.88 (t, Jꢃ
1.39 (m, 8H), 1.73 (penta, Jꢃ4.50
7.96 (m, 5H)
/
4.20 Hz, 3H), 1.28ꢀ
/
/
Hz, 2H), 2.95 (t, Jꢃ
/
4.50 Hz, 2H), 7.43ꢀ
/
ppm. 13C-NMR: d 13.98, 22.56, 24.35, 29.09, 29.29,
3.5.2. 3-(4?-Bromophenyl)-2-phenylpropan-2-ol (5b)
Pale-brown oil. H-NMR (300 MHz, CDCl3, 25 8C):
31.65, 38.56, 127.99, 128.48, 132.76, 137.13, 200.46 ppm.
1
dꢃ
/
1.59 (s, 3H), 3.04 (q, Jꢃ
/
13.50 Hz, 2H), 6.85ꢀ
/
7.41
3.5.9. 1-Phenyl-1-octanol (7b)
(m, 9H) ppm. 13C-NMR: d 29.18, 49.78, 74.33, 120.56,
124.88, 126.74, 128.04, 130.90, 132.20, 135.77, 147.00
ppm.
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.89 (t, Jꢃ
1.79 (m, 2H), 1.94
7.36 (m,
/
6.90 Hz, 3H), 1.27 (br s, 10H), 1.71ꢀ
/
(s, 1H), 4.66 (dd, Jꢃ
/
13.20, 1.20 Hz, 1H), 7.26ꢀ
/
5H) ppm. 13C-NMR: d 14.05, 22.61, 25.81, 29.18, 29.46,
3.5.3. 3-(4?-Bromophenyl)-2-phenylpropan-2-ol (5c)
Pale-yellow solid; m.p.: 55-56 8C. 1H-NMR (300
31.78, 39.08, 74.67, 125.87, 127.43, 128.39, 144.93 ppm.
MHz, CDCl3, 25 8C): dꢃ
2.99 (d, Jꢃ6.90 Hz, 2H), 4.84 (t, Jꢃ
7.08ꢀ
7.36 (m, 9H) ppm. 13C-NMR: d 45.03, 75.13,
125.81, 127.67, 128.39, 130.80, 132.26, 136.41, 143.45
ppm.
/
2.14 (d, Jꢃ
/
4.20 Hz, 1H),
6.60 Hz, 1H),
3.5.10. Decyl phenyl ketone (7c)
/
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.88 (t, Jꢃ
1.34 (m, 14H), 1.73 (penta, Jꢃ7.20
7.97 (m, 5H)
/
/
6.00 Hz, 3H), 1.26ꢀ
/
/
Hz, 2H), 2.95 (t, Jꢃ
/
7.20 Hz, 2H), 7.41ꢀ
/
ppm. 13C-NMR: d 14.00, 22.58, 24.27, 29.23, 29.29,
29.42, 29.49, 31.80, 38.49, 127.94, 128.42, 132.71,
136.99, 200.34 ppm.
3.5.4. 3-(4?-Chlorophenyl)-2-phenylpropan-2-ol (5d)
1
Pale-brown oil. H-NMR (300 MHz, CDCl3, 25 8C):
dꢃ
2H), 6.90ꢀ
/
1.58 (s, 3H), 1.89 (br s, 1H), 3.05 (q, Jꢃ
/
13.50 Hz,
7.41 (m, 9H) ppm. 13C-NMR: d 29.23, 49.74,
3.5.11. 10-Undecyl phenyl ketone (7d)
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.29ꢀ
7.20 Hz, 2H), 2.04 (q, Jꢃ
7.20 Hz, 2H), 4.91ꢀ5.03 (m,
5.86 (m. 1H), 7.43ꢀ
7.98 (m, 5H) ppm. 13C-
/
1.44
74.40, 124.89, 126.76, 127.98, 128.05, 131.81, 132.42,
135.24, 147.04 ppm. HRFAB Calc. for C15H15ClO
246.0811, Found: [Mꢁ
(m, 12H), 1.74 (penta, Jꢃ
6.60 Hz, 2H), 2.96 (t, Jꢃ
2H), 5.77ꢀ
/
/
/
/
/
Li]ꢁ 253.0969.
/
/

32
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
NMR: d 24.32, 28.88, 29.07, 29.33, 29.40, 33.75, 38.57,
114.08, 128.01, 128.50, 132.85, 137.06, 139.17, 200.53
ppm.
3.6.2. 2-(3-Methoxyphenyl)-1-phenyl ethanone (9b)
B.p. 140ꢀ
143 8C (0.27 mmHg); IR(KBr) 1675 cmꢄ1
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
3.73 (s, 3H),
4.03 (s, 2H), 6.66ꢀ6.93 (m, 3H), 7.09ꢀ7.64 (m, 4H),
7.90ꢀ8.11 (m, 2H) ppm. HRMS 226.0994, Calc. for
/
.
/
/
/
/
3.5.12. Cyclohexylmethyl phenyl ketone (7e)
C15H14O2 226.0994.
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.99ꢀ
1.79 (m, 5H), 1.98 (m, 1H), 2.82 (d, Jꢃ
6.60 Hz, 2H), 7.42ꢀ
7.96 (m, 5H) ppm. 13C-NMR: d
/
1.31
(m, 5H), 1.64ꢀ
/
/
3.6.3. 2-(4-Methylphenyl)-1-phenyl ethanone (9c)
/
M.p.: 95ꢀ
NMR (300 MHz, CDCl3, 25 8C): dꢃ
(s, 2H), 7.03ꢀ7.70 (m, 7H), 7.95ꢀ8.20 (m, 2H) ppm.
/
96 8C; IR(KBr) 1685 cmꢄ1(CÄ
/
O). 1H-
26.07, 26.19, 33.35, 34.44, 46.10, 128.04, 128.43, 132.74,
137.42, 200.11 ppm.
/
2.32 (s, 3H), 4.23
/
/
3.6.4. 1-Phenyl-2-(2-pyridinyl)-ethanone (9d)
M.p.: 52ꢀ
54 8C. 1H-NMR (300 MHz, CDCl3, 25 8C):
3.5.13. 4-Phenylbutyl phenyl ketone (7f)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.75ꢀ
7.80 Hz, 2H), 3.01 (t, Jꢃ6.60 Hz,
7.99 (m, 10H) ppm. 13C-NMR: d 23.90,
/
1.83
/
dꢃ
/
4.50 (s, 2H), 6.06 (s, enolic Ã
/
CHÄ
/
), 6.92ꢀ8.60 (m,
/
(m, 4H), 2.74 (t, Jꢃ
/
/
10H) ppm. EIMS m/z (relative intensity) 197 [Mꢁ, 15],
169 (30), 168 (36), 120 (8), 105 (100), 92 (12), 77 (68).
2H), 7.21ꢀ
/
31.02, 37.73, 38.31, 125.68, 127.96, 128.24, 128.34,
128.49, 132.84, 136.96, 142.17, 200.17 ppm.
3.6.5. 4-Chlorobenzyl pentadecyl ketone (9e)
White solid; m.p.: 56ꢀ
/
58 8C; IR(KBr) 1680 cmꢄ1 (CÄ
/
O). 1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.9 (t, 3H),
3.5.14. 1,5-Diphenyl-1-pentanol (7g)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.33ꢀ
7.20 Hz, 2H), 4.67
7.42 (m, 5H) ppm.
/
1.89
1.25 (m. 26H), 2.48 (t, 2H), 3.69 (s, 2H), 7.12ꢀ
/
7.36 (m,
4H) ppm. 13C-NMR: d 14.05, 23.95, 29.88, 30.03, 32.51,
40.73, 46.63, 129.70, 130.35, 132.23, 132.47, 207.12 ppm.
(m, 6H), 2.07 (br s, 1H), 2.64 (t, Jꢃ
/
(dd, Jꢃ
/
13.20, 1.20 Hz, 2H), 7.19ꢀ
/
13C-NMR: d 25.46, 31.34, 35.78, 38.83, 74.46, 125.58,
125.81, 127.44, 128.20, 128.31, 128.37, 142.50, 144.79
ppm.
3.6.6. 4-Fluoro-a-phenyl benzeneethanol (10a)
M.p.: 45 8C. 1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.82 (br s, 1H), 2.99(d, Jꢃ
/
6.90 Hz, 2H), 4.86 (t, Jꢃ
/6.90
Hz, 1H), 6.92ꢀ
/
7.01 (m, 2H), 7.08ꢀ
/
7.16 (m, 2H), 7.26ꢀ
/
3.6. Typical preparation of benzylic manganese
phosphates and their cross-coupling reactions
7.38 (m, 5H) ppm. 13C-NMR: d 45.01, 75.33, 115.22,
125.91, 127.67, 128.34, 130.80, 133.66, 143.61, 161.45.
HRMS 216.2440, Found: 216.2444 ppm.
Benzyl diethyl phosphate (9 mmol) was added via a
syringe to the slurry of highly active manganese (10
mmol) being stirred in THF (12 ml) at r.t. The slurry
was stirred overnight at r.t. The reaction was monitored
by TLC and/or GC. After the completion of the
oxidative addition, the mixture was cooled to 0 8C using
an ice bath. 1,2-Dibromoethane was added to the
mixture at this temperature, and the mixture was stirred
for 5 min. To the reaction mixture was added an
appropriate electrophile (8 mmol) through a syringe.
After being stirred for 1 h, the mixture was quenched
with 2 M HCl solution and extracted with diethyl ether.
The combined organic layers were washed with
NaHCO3, Na2S2O3, and brine, dried over anhydrous
MgSO4, and concentrated using a rotary evaporator.
Flash column chromatography (ethyl acetate/hexanes)
afforded the corresponding product.
3.6.7. 4-Fluoro-a-phenyl benzeneethanol (10b)
M.p.: 43ꢀ
dꢃ2.07 (br s, 1H), 2.29(s, 3H), 2.90 (d, Jꢃ
2H), 4.78 (t, Jꢃ6.10 Hz, 1H), 7.02 (s, 4H), 7.26 (s, 5H)
/
45 8C. 1H-NMR (300 MHz, CDCl3, 25 8C):
/
/
6.11 Hz,
/
ppm. EIMS m/z (relative intensity) 77 (33), 79 (41), 91
(26), 103 (5), 104 (3), 105 (19), 106 (100), 107 (39).
3.7. Homo-coupling reactions of functionalized benzyl
halide
The slurry of active manganese (2 mmol) in 15 ml of
THF was added to benzyl halides (3.8 mmol) and the
reaction mixture was stirred at r.t. The reaction progress
was monitored by Gas chromatography. After being
stirred for 10 min, the reaction mixture was quenched
with saturated ammonium chloride aqueous solution
and the organic layer was extracted with diethyl ether
3.6.1. 4-Chlorobenzyl phenyl ketone (9a)
(2ꢂ10 ml). The combined organic layers were washed
/
1
M.p.: 55ꢀ
MHz, CDCl3, 25 8C): dꢃ
7H), 7.93ꢀ
8.13 (m, 2H) ppm. 13C-NMR: d 44.43,
/
56 8C; IR(KBr) 1675 cmꢄ1. H-NMR (300
with saturated sodium thiosulfate aqueous solution (10
ml) and dried over anhydrous magnesium sulfate and
concentrate using rotary evaporator. Flash column
chromatography (hexane/ethyl acetate) or recrystalliza-
tion afforded the corresponding bibenzyls.
/
4.24 (s, 2H), 7.10ꢀ7.75 (m,
/
/
128.49, 128.84, 129.48, 129.60, 131.22, 133.76, 133.92,
134.39, 137.54, 137.54, 196.55 ppm.

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
33
3.7.1. 1,2-bis(4-Cyanophenyl)ethane (11a)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
7.21ꢀ
7.58 (m, 8H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ37.15, 110.25, 118.80, 129.20, 132.26, 146.03
ppm.
3.7.10. 1,2-bis(3,5-Dimethoxyphenyl)ethane (11j)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.86 (s, 4H),
3.80 (s, 12H), 6.31ꢀ
6.39 (m, 6H) ppm. 13C-NMR (75
MHz, CDCl3, 25 8C): dꢃ38.48, 56.01, 98.61, 107.33,
144.55, 147.68, 161.92 ppm.
/3.00 (s, 4H),
/
/
/
/
/
3.7.11. 1,2-bis(2-Methylphenyl)ethane (11k)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.34 (s, 6H),
2.86 (s, 4H), 7.10ꢀ
7.23 (m, 8H) ppm. 13C-NMR (75
MHz, CDCl3, 25 8C): dꢃ20.08, 34.55, 126.75, 129.88,
131.10, 137.23, 141.50 ppm.
3.7.2. 1,2-bis(3-Cyanophenyl)ethane (11b)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
7.33ꢀ
7.53 (m, 8H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ36.77, 112.51, 118.72, 129.23, 130.10, 131.88,
/
/2.97 (s, 4H),
/
/
/
/
132.97, 141.85 ppm.
3.8. Typical preparation of functionalized benzylic
manganese halides and their cross-coupling reactions with
aryl iodides under palladium catalyst
3.7.3. 1,2-bis(2-Cyanophenyl)ethane (11c)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
3.17 (s, 4H),
7.53 (m, 2H), 7.59ꢀ7.62 (m,
2H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
7.29ꢀ
/
7.34 (m, 4H), 7.47ꢀ
/
/
/
Benzyl halide (1.8 mmol) in THF (10 ml) was added
via cannula to a slurry of active manganese (2 mmol)
being stirred in THF (10 ml) at r.t. The reaction mixture
was stirred at r.t. for 20 min. The reaction progress was
monitored by Gas chromatography. After the comple-
tion of the oxidative addition, the mixture was cooled to
0 8C using ice-bath. 1,2-Dibromoethane was added to
the mixture via syringe and the mixture was allowed to
stir for 5 min. The resulting mixture was added via a
cannula to a mixture of aryl iodides (1.2 mmol) and 5
mol.% of Pd(PPh3)4 catalyst in THF (10 ml). The
mixture was stirred at r.t. for 2 h. An saturated aqueous
solution of ammonium chloride (10 ml) was added then
36.12, 112.83, 118.32, 127.61, 130.37, 133.33
3.7.4. 2,3-Diphenylbutane (11d)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.03ꢀ
7.37 (m, 10H) ppm.
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
21.02, 47.23,
126.03, 127.60, 128.27, 146.48 ppm.
/
1.06
(m, 6H), 2.80ꢀ
/
2.84 (m, 2H), 7.23ꢀ
/
/
3.7.5. 1,2-bis(4-Carbomethoxyphenyl)ethane (11e)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.97 (s, 4H),
3.89 (s, 6H), 7.18 (d, Jꢃ8.11 Hz, 4H), 7.93 (d, Jꢃ8.11
Hz, 4H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
/
/
/
the mixture was extracted with diethyl ether (2ꢂ10 ml).
/
37.94, 52.55, 128.65, 129.09, 130.28, 147.07, 167.57 ppm.
The combined organic layers were washed with satu-
rated aqueous solution of sodium thiosulfate (10 ml),
then dried over magnesium sulfate. Removal of solvents
and flash column chromatography (hexane/ethyl ace-
tate) afforded diarylmethane.
3.7.6. 1,2-bis(4-Nitrophenyl)ethane (11f)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
3.09 (s, 4H),
8.82 Hz, 4H) ppm.
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
37.59, 124.46,
129.96, 147.33, 148.75 ppm.
7.29 (d, Jꢃ
/
8.82 Hz, 4H), 8.14 (d, Jꢃ
/
/
3.8.1. Ethyl 4-benzylbenzoate (12a)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.42 (t, Jꢃ
7.15 Hz, 2H),
8.05 (m, 9H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ14.22, 41.77, 60.68, 126.25, 128.34, 128.49,
/
7.15 Hz, 3H), 4.06 (s, 2H), 4.41 (q, Jꢃ
/
3.7.7. 1,2-bis(4-Bromophenyl)ethane (11g)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
6.97ꢀ7.02 (m, 4H), 7.37ꢀ
7.42 (m, 4H) ppm. 13C-NMR
(75 MHz, CDCl3, 25 8C): dꢃ37.91, 120.52, 131.67,
132.15, 140.80 ppm.
7.20ꢀ
/
/
2.77 (s, 4H),
/
/
/
128.79, 128.82, 129.68, 140.06, 146.27, 166.42 ppm.
HRMS Calc. for C16H16O2 240.1150, Found: 240.1151.
/
3.8.2. Ethyl 4-(4?-bromobenzyl)benzoate (12b)
3.7.8. 1,2-bis(4-Chlorophenyl)ethane (11h)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
SiMe3), 7.06ꢀ7.19 (m, 4H), 7.22ꢀ7.28 (m, 4H) ppm.
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
37.89, 129.22,
130.65, 132.48, 140.46 ppm.
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.39 (t, Jꢃ
7.15 Hz, 2H),
8.00 (m, 8H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ14.27, 41.18, 60.80, 120.19, 128.63, 128.78,
/
/2.85 (s, 4H,
7.15 Hz, 3H), 3.98 (s, 2H), 4.37 (q, Jꢃ
/
/
/
7.03ꢀ
/
/
/
129.00, 129.81, 129.99, 130.58, 131.60, 139.10, 145.56,
166.39 ppm.
3.7.9. 1,2-bis(2,6-Dichlorophenyl)ethane (11i)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
3.26 (s, 4H),
7.05ꢀ7.14 (m, 2H), 7.23ꢀ
7.34 (m, 4H) ppm. 13C-NMR
(75 MHz, CDCl3, 25 8C): dꢃ30.20, 128.78, 128.98,
136.89, 137.48 ppm.
/
3.8.3. 3-(3?,5?-Dimethoxybenzyl)benzonitrile (12c)
/
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
3.78 (s, 6H),
7.51 (m, 4H) ppm.
13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
42.14, 55.87,
/
3.94 (s, 2H), 6.32ꢀ
/
6.38 (m, 3H), 7.36ꢀ
/
/

34
Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ36
/
98.83, 107.74, 113.05, 119.54, 129.82, 130.58, 132.89,
133.98, 142.26, 144.71, 161.66 ppm.
(t, Jꢃ
/
7.39 Hz, 2H), 3.59 (s, 2H), 3.78 (s, 6H), 6.35 (br s,
3H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
/
14.08, 22.65, 23.70, 29.07, 29.32, 29.42, 29.55, 29.61,
29.64, 31.88, 41.76, 50.42, 55.25, 98.93, 107.37, 136.49,
160.91, 208.45 ppm.
3.8.4. Ethyl 4-(4?-chlorobenzyl)benzoate (12d)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.42 (t, Jꢃ
7.15 Hz, 2H),
8.01 (m, 8H) ppm. 13C-NMR (75 MHz, CDCl3,
25 8C): dꢃ14.47, 41.88, 61.78, 129.66, 129.69, 130.76,
/
7.15 Hz, 3H), 4.05(s, 2H), 4.37 (q, Jꢃ
/
7.09ꢀ
/
/
3.9.5. 2-(3,5-Dimethoxyphenyl)-1-phenylethan-1-ol (14)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.09 (br s,
131.11, 133.01, 139.66, 146.56, 167.34 ppm.
/
1H), 2.88ꢀ
/
3.03 (m, 2H), 3.76 (s, 6H), 4.88, 4.91 (dd, Jꢃ
/
3.9. Typical procedure for the coupling reaction of 1f with
4.76 Hz, 4.77 Hz, 1H), 6.36 (br s, 3H), 7.26ꢀ
/
7.28 (m,
aldehydes and acid chlorides (13aꢀ
/
13d, 14ꢀ
/
18)
5H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
46.40, 55.21, 55.24, 75.03, 98.67, 107.36, 125.87,
127.57, 128.75, 140.25, 143.70, 160.80 ppm.
/
The benzylic manganese reagent was prepared as
before. To the resulting benzylic reagents was added
the aldehydes (or acid chloride) at r.t. After being stirred
for 1 h, the mixture was quenched with 2 M HCl
solution and extracted with diethyl ether. The combined
organic layers were washed with saturated aqueous
solution of sodium thiosulfate (10 ml), then dried over
magnesium sulfate. Removal of solvents and flash
column chromatography (hexane/ethyl acetate) afforded
the corresponding coupling product.
3.9.6. 2-(3,5-Dimethoxyphenyl)-1-(3?-
methoxyphenyl)ethan-1-ol (15)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
2.35 (br s,
2.96 (m, 2H), 3.75, 3.80 (ss, 9H), 4.83, 4.86
4.77 Hz, 5.01 Hz, 1H), 6.36 (br s, 3H), 6.81ꢀ
7.29 (m, 4H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C):
dꢃ46.20, 55.08, 74.81, 98.52, 107.27, 111.14, 112.99,
1H), 2.91ꢀ
/
(dd, Jꢃ
/
/
/
118.10, 129.25, 140.22, 145.43, 159.52, 160.62 ppm.
3.9.1. 1-(3,5-Dimethoxyphenyl)-2-hydroxytridecane
(13a)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.88 (t, Jꢃ
1.52 (m, 20H), 1.60 (br s, 1H), 2.54,
8.59 Hz, 8.58 Hz, 1H), 2.75, 2.80 (dd, Jꢃ
3.81 Hz, 3.82 Hz, 1H), 3.78 (s, 7H), 6.35ꢀ6.37 (m, 3H)
ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
14.09,
/
3.9.7. 2-(3,5-Dimethoxyphenyl)-1-(4?-
methoxyphenyl)ethan-1-ol (16)
5.96 Hz, 3H), 1.26ꢀ
/
2.58 (dd, Jꢃ
/
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
2.17 (br s,
/
/
1H), 2.91ꢀ
/
2.94 (m, 2H), 3.75, 3.80 (ss, 9H), 4.83 (t, Jꢃ
/
/
7.39 Hz, 1H), 6.35 (br s, 3H), 6.81, 7.27 (dd, Jꢃ11.45
Hz, 8.58 Hz, 4H) ppm. 13C-NMR (75 MHz, CDCl3,
/
22.66, 25.75, 29.33, 29.61, 29.64, 31.89, 36.84, 44.36,
55.24, 72.48, 98.38, 107.30, 140.99, 160.89 ppm.
25 8C): dꢃ46.27, 55.15, 74.62, 98.54, 107.31, 113.66,
/
128.08, 135.91, 140.41, 158.95, 160.70 ppm.
3.9.2. 1-(3,5-Dimethoxyphenyl)-2-hydroxypentadecane
(13b)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.89 (t, Jꢃ
1.53 (m, 24H), 1.62 (s, 1H), 2.54,
8.58 Hz, 8.82 Hz, 1H), 2.75, 2.80 (dd, Jꢃ
4.06 Hz, 4.05 Hz, 1H), 3.78 (s, 7H), 6.35ꢀ6.38 (m, 3H)
ppm. 13C-NMR (75 MHz, CDCl3, 25 8C): dꢃ
14.08,
/
3.9.8. 1-(3,4-Dimethoxyphenyl)-2-(3?,5’-
dimethoxyphenyl)ethan-1-ol (17)
6.20 Hz, 3H), 1.26ꢀ
/
2.59 (dd, Jꢃ
/
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
2.16 (br s,
2.94 (m, 2H), 3.73, 3.86 (ss, 12H), 4.81, 4.83
5.40 Hz, 5.49 Hz, 1H), 6.34 (br s, 3H), 6.80ꢀ
6.90 (m, 3H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C):
dꢃ46.33, 55.15, 55.75, 55.82, 74.81, 98.52, 107.73,
/
1H), 2.90ꢀ
/
/
(dd, Jꢃ
/
/
25.74, 29.33, 29.64, 31.89, 36.84, 44.36, 55.21, 72.47,
98.36, 107.28, 140.98, 160.87 ppm.
/
108.94, 110.79, 118.04, 136.39, 140.32, 148.31, 148.85,
160.73 ppm.
3.9.3. 1-(3,5-Dimethoxyphenyl)-pentadecan-2-one (13c)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
0.88 (t, Jꢃ
1.25 (m, 20H), 1.53 (br s, 2H), 2.44
7.39 Hz, 2H), 3.60 (s, 2H), 3.78 (br s, 6H), 6.35
(br s, 3H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C):
dꢃ14.06, 22.65, 23.70, 29.05, 29.32, 29.42, 29.59, 31.88,
/
6.90 Hz, 3H), 1.23ꢀ
/
(t, Jꢃ
/
3.9.9. 1-(4-Benzyloxy-3-methoxyphenyl)-2-(3?,5?-
dimethoxyphenyl)ethan-1-ol (18)
/
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
2.45 (br s,
6.44 Hz, 2H), 3.72, 3.86 (ss, 9H), 4.79
6.68 Hz, 1H), 5.14 (s, 2H), 6.35 (br s, 3H), 6.78ꢀ
7.46 (m, 8H) ppm. 13C-NMR (75 MHz, CDCl3, 25 8C):
dꢃ46.08, 54.96, 55.69, 70.72, 74.61, 98.33, 107.21,
41.76, 50.42, 55.25, 98.93, 107.28, 136.49, 160.93, 208.46
ppm.
1H), 2.92 (d, Jꢃ
/
(t, Jꢃ
/
/
3.9.4. 1-(3,5-Dimethoxyphenyl)-heptadecan-2-one (13d)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
/
0.88 (t, Jꢃ
/
109.42, 113.50, 117.88, 127.03, 127.57, 128.27, 136.92,
140.25, 147.18, 149.33, 160.49 ppm.
5.72 Hz, 3H), 1.23ꢀ/1.25 (m, 24H), 1.59 (br s, 2H), 2.43

Y. Suh et al. / Journal of Organometallic Chemistry 684 (2003) 20ꢀ
/36
35
3.10. Typical procedure for addtion reactions of benzyl
manganese reagents to N-ethoxy-carbonylpyridinium
more importantly, benzyl alcohols can be used to make
benzylic manganese reagents via direct oxidative addi-
tion of Mn* to benzyl sulfonates and phosphates. The
reactions of the resulting benzylic manganese reagents
proceed with good to excellent yields with several
electrophiles in the absence of any catalyst and in
some cases without any solvent. It has been found that
this approach can be also used for the preparation of
resorcinolic lipid derivatives, and bibenzyl lipid deriva-
tives as well as substituted 1,4-dihydropyridines, and/or
4-benzylpyridines.
salts (19aꢀ19c)
/
To the slurry of activated manganese in THF (20 ml)
was added a solution of BnBr (13 mmol) at r.t. After
stirring under argon atmosphere for 1 h, this solution
was added to a preformed solution of pyridinium
chloride (from ethyl chloroformate (10 mmol), pyridine
(10 mmol), THF (40 ml), at ꢄ
/
30 8C for 30 min) at ꢄ
/
30 8C. The mixture was warmed up slowly to r.t. and
was allowed to stand overnight (10 h). Additional
CH2Cl2 (20ꢀ30 ml) was added to the mixture, and the
/
whole was washed with water and dried Na2SO4. After
the solvent was evaporated, the residue was chromato-
graphed on silica gel.
Acknowledgements
We are grateful of the National Science Foundation
for support of this work.
3.10.1. 4-Benzyl-N-ethoxycarbonyl-1,4-dihydropyridine
(19a)
1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
/
1.34 (t, Jꢃ
7.00 Hz, 2H), 3.20ꢀ3.31 (m,
7.15 Hz, 2H), 4.58ꢀ4.96 (m, 2H), 6.90
8.01 Hz, 2H), 7.14ꢀ
7.39 (m, 5H) ppm. 13C-NMR
(75 MHz, CDCl3, 25 8C): dꢃ13.33, 34.96, 41.07, 60.68,
/
References
7.15 Hz, 3H), 2.76 (d, Jꢃ
1H), 4.24 (q, Jꢃ
(d, Jꢃ
/
/
/
/
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/
/
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110.71, 111.22, 122.45, 121.88, 126.25, 128.34, 129.18,
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3.10.2. 4-(4?-Chlorobenzyl)-N-ethoxycarbonyl-1,4-
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1H-NMR (300 MHz, CDCl3, 25 8C): dꢃ
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1.33 (t, Jꢃ
7.00 Hz, 2H), 3.20ꢀ3.33 (m,
7.15 Hz, 2H), 4.58ꢀ4.96 (m, 2H), 6.91
8.01 Hz, 2H), 7.14ꢀ
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/
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7.15 Hz, 3H), 2.77 (d, Jꢃ
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(d, Jꢃ
/
/
/
/
/
/
(d) M.J. Gallagher, S. Harvey, C.L. Raston, R.E. Sue, J. Chem.
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/
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110.71, 111.22, 122.45, 121.88, 128.49, 129.48, 139.05,
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/
1.38 (t, Jꢃ
/
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(m, 2H), 6.90 (d, Jꢃ8.01 Hz, 2H), 7.11ꢀ
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/
7.01 Hz, 2H), 3.20ꢀ
/
3.33 (m,
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/
7.15 Hz, 2H), 4.60ꢀ
/
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/
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36
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