Triaminocyclopentadienyl Ruthenium Complexes – New Catalysts for Cascade Conversions of Propargyl Alcohols

Article abstract of DOI:10.1002/chem.202102959

Various triaminocyclopentadienyl ruthenium complexes have been synthesized from Ru₃(CO)₁₂. The new complexes were tested for their ability to catalyze cascade conversions of propargyl alcohols. Their associated catalytic activities complement the activities of known diaminocyclopentadienone ruthenium complexes. In particular, the substrate scope of catalytic cycloadditions with 3-ketolactones or phloroglucinol derivatives is extended to terpenoid-derived propargyl alcohols containing an internal alkyne moiety. A wide range of cyclic terpenoid and phloroglucinol adducts are obtained by complementary application of both types of catalysts.

Full text of DOI:10.1002/chem.202102959

Accepted Article
Accepted Article
Title: Triaminocyclopentadienyl Ruthenium Complexes – New
Catalysts for Cascade Conversions of Propargyl Alcohols
Authors: Edgar Haak, Jana Hatzfeld, Steffen Skowaisa, Elisabeth
Jäckel, and Julia Kaufmann
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Chem. Eur. J. 10.1002/chem.202102959
Link to VoR: https://doi.org/10.1002/chem.202102959
01/2020

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
Triaminocyclopentadienyl Ruthenium Complexes – New Catalysts
for Cascade Conversions of Propargyl Alcohols
Jana Hatzfeld, Steffen Skowaisa, Elisabeth Jäckel, Julia Kaufmann and Edgar Haak*[a]
Abstract: Various triaminocyclopentadienyl ruthenium complexes
have been synthesized from Ru3(CO)12. The new complexes were
tested for their ability to catalyze cascade conversions of propargyl
alcohols. Their associated catalytic activities complement the
activities of known diaminocyclopentadienone ruthenium complexes.
In particular, the substrate scope of catalytic cycloadditions with
3-ketolactones or phloroglucinol derivatives is extended to terpenoid-
derived propargyl alcohols containing an internal alkyne moiety. A
wide range of cyclic terpenoid and phloroglucinol adducts are
obtained by complementary application of both types of catalysts.
generates allenylidene species III. Secondary derivatives 2 (R1,
R2=H) are alternatively transformed in a redox-isomerization
process to generate alkenyl species IV. Internal substrates 2
(R1≠H) are activated via -complex V. Subsequent trapping of the
metalated intermediates I-V with various nucleophiles give rise to
diverse carbo- and heterocyclic compounds with release of the
catalytically active species.[4] Thus, in presence of cyclic 1,3-
dicarbonyl compounds, terminal secondary substrates 2 (R1,
R2=H) form Michael-adducts
whereas terminal tertiary substrates
3
or spirocyclohexanones 4,
(R1=H, R2≠H) are
2
converted to methylene spirocyclopentenes 5 in an allylation /
carbocyclization cascade. Internal secondary substrates 2 (R1≠H,
R2=H) form 4H-pyrans 6 with cyclic 1,3-dicarbonyl compounds in
a formal cycloaddition process (Scheme 1).
Introduction
Transition metal-catalyzed cascade reactions provide an
atomeconomical approach to the efficient synthesis of complex
molecular scaffolds. Such transformations are particularly
suitable for the preparation of natural products and analogues as
important lead structures in the context of drug discovery.[1,2] With
regard to the multiply functionalized precursors required for the
desired cascade conversions, 1-alkenylpropargyl alcohols (1-en-
4-yn-3-ols) are particularly noteworthy. These enynols are directly
accessible from
a broad range of readily available,-
unsaturated aldehydes or ketones by acetylide addition. All
carbon atoms of this versatile C5 subunit are selectively
addressable with the aid of various transition-metal catalysts. Due
to the presence of three different functional groups, several
modes of activation can be applied, giving rise to diverse cascade
transformations.[3]
Ruthenium cyclopentadienone complexes of type 1 catalyze
diverse cascade conversions of 1-alkenylpropargyl alcohols 2
with various nucleophiles.[4] An acidic promoter is beneficial in
most cases. The redox-coupling between the metal and the ligand
in complexes of type 1 is crucial for all of these conversions and
the activation of the alkyne unit in 2 depends most likely on
electrophilic ruthenium(II) species 1’ that is privileged under acidic
conditions (Scheme 1). The mode of activation depends on the
nature of the substrate. Terminal propargyl alcohols 2 (R1=H) are
converted via alkynyl complex I, which is in equilibrium with the
corresponding vinylidene compound II. Subsequent loss of water
Scheme 1. Activation and conversion of propargyl alcohols 2 catalyzed by
ruthenium cyclopentadienone complexes 1.
[a]
J. Hatzfeld, Dr. E. Jäckel, Dr. J. Kaufmann, S. Skowaisa, Prof. Dr. E.
Haak
Institut für Chemie, Otto-von-Guericke-Universität Magdeburg
Universitätsplatz 2, 39106 Magdeburg (Germany)
E-mail: edgar.haak@ovgu.de
Exchange of the ligand’s carbonyl oxygen for nitrogen should
dramatically effect the redox-coupling with the metal and could
thereby alter the catalyst’s mode of action. Herein, we present
various triaminocyclopentadienyl ruthenium(II) complexes of type
Supporting information for this article is given via a link at the end of
the document.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
7 and compare some of their catalytic activities with the activity of
diamino-cyclopentadienone catalyst 1a (Scheme 2). Complexes
of type 7 can be regarded as aza analogues of the activated
species 1’.
Results and Discussion
The ligands L7 are generated from cyclopentadienone L1a by a
modified protocol of the method from GOMPPER et. al.[5]
Complexes 7 are formed from iminium precursors L7 as formal
ruthenium(II) species, whereas catalysts of type 1 derived from
cyclopentadienone precursors L1 arise as formal ruthenium(0)
complexes (Scheme 2).[4c,6]
Figure 1. Prepared triaminocyclopentadienyl ruthenium(II) complexes (7).
Scheme 2. Synthesis of complex 1a and aza-derivatives 7.
Next, we compared some of the catalytic activities of the new
catalysts 7 towards 1-alkenylpropargyl alcohols 2 with those of
catalyst 1a. We based the first systematic comparative study on
the allylation / carbocyclization cascade of terminal tertiary
1-alkenylpropargyl alcohols 2 with cyclic carbon nucleophiles.
Conversion of alcohol 2a with 1,3-cyclohexandione (A) in toluene
(1.0 M) at 100°C in presence of catalyst 1a (2 mol-%) and
trifluoroacetic acid (TFA, 4 mol-%) as an acidic promoter,
generates compound 5Aa[4e] in 82% yield (Scheme 3; Table 1,
entry 3). No conversion was observed in absence of the catalyst
and a significantly lower yield was obtained in absence of the
acidic promoter (Table 1, entries 1, 2). At 170°C (microwave
irradiation) a significant lower yield is obtained (Table 1, entry 4).
Complex 1a shows high long-term stability at higher temperature
and no decomposition is observed at 170°C in toluene about 20
h. However, in presence of the acidic promoter (2 eq.),
decomposition occurs at elevated temperatures. At 170°C, 49%
of 1a remained after 5 minutes, 34% after 10 minutes and 25%
after 15 minutes (determined by NMR using an internal standard).
Only small amounts of product 5Aa are obtained if Ru3(CO)12,
[Ru(CO)3Cl2]2 or the tetracyclone complex Tcc were applied as
catalysts under similar reaction conditions (Table 1, entries 5-10).
Exemplary aza-catalyst 7j was applied in absence of an acidic
promoter, since a counterproductive effect has been observed
(Table 1, entries 11-13). Unfortunately, only low yields of 5Aa are
obtained at 100°C, as well as at 170°C, even though complex 7j
shows no remarkable decomposition at 170°C.
Various primary amines are suitable for this conversion including
enantiopure derivatives. The range of appropriate secondary
amines, however, is rather limited due to strong steric repulsion
in the planar iminium compounds L7. Further conversion of L7
with ruthenium carbonyl results in the formation of the desired
triaminocyclopentadienyl complexes 7 in almost all cases. The
highest yields are obtained from ligand L7j and complex 7j can
be easily prepared in racemic or enantiopure (R)- or (S)-form from
inexpensive commercially available amines. Therefore, complex
7j was used as an exemplary representative of the aza-catalysts
7. Broadening of the corresponding NMR-signals indicates a
significant hindrance to the rotation of the phenyl groups in all
complexes of type 7. Formation of complex 7o is not successful
due to the metal chelating effect of the guanidine unit (Figure 1).
We previously reported on the related synthesis of N-
unsubstituted complex 7a.[4c]
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
observed at higher concentration. In contrast, full conversion is
observed at a concentration of 1.0 M with less active complex 7j
(Table 2, entries 10, 11, 18). Therefore, complex 7j represents a
good compromise in terms of stability, activity, and availability.
Scheme 4. Conversion of propargyl alcohol 2a with 4-hydroxycoumarin (B).
Table 2. Formation of compound 5Ba applying different catalysts.
Scheme 3. Conversion of propargyl alcohol 2a with 1,3-cyclohexanedione (A).
Table 1. Formation of compound 5Aa applying different catalysts.
No
catalyst
1a
1a
1a
1a
1a
7a
7b
7c
7d
7e
7e
7f
promoter
TFA
concentration
1.0 M
conversion[a]
100%
98%
Yield 5aB
91%[d]
87%[e]
69%[e]
45%[e]
36%[e]
25%[e]
24%[e]
42%[e]
41%[e]
73%[e]
70%[e]
17%[e]
24%[e]
54%[e]
19%[e]
35%[e]
22%[e]
89%[d]
23%[e]
15%[e]
21%[e]
18%[e]
1[b]
No
1
catalyst
promoter
TFA
conditions[a]
100°C, 5 h
Yield 5Aa
n.c.
2[c]
TFA
1.0 M
none
3[c]
TFA
0.5 M
79%
2
1a
none
TFA
100°C, 5 h
31%[b]
82%[c]
19%[b]
5%[b]
4[c]
TFA
0.25 M
0.25 M
0.25 M
0.25 M
0.25 M
0.25 M
0.25 M
1.0 M
56%
3
1a
100°C, 5 h
5[c]
none
none
none
none
none
none
none
none
none
none
none
none
TFA
58%
4
1a
TFA
170°C, 15 min
100°C, 5 h
6[c]
30%
5
Ru3(CO)12
TFA
7[c]
32%
6
Ru3(CO)12
TFA
170°C, 15 min
100°C, 5 h
5%[b]
8[c]
50%
7
[RuCl(CO)3]2
TFA
3%[b]
9[c]
53%
8
[RuCl(CO)3]2
TFA
170°C, 15 min
100°C, 5 h
4%[b]
10[c]
11[c]
12[c]
13[c]
14[c]
15[c]
16[c]
17[c]
18[c]
19[c]
20[c]
21[c]
22[c]
83%
9
Tcc
Tcc
7j
TFA
10%[b]
12%[b]
15%[b]
19%[b]
8%[b]
95%
10
11
12
13
TFA
170°C, 15 min
100°C, 5 h
0.25 M
0.25 M
0.25 M
0.25 M
0.25 M
0.25 M
1.0 M
24%
TFA
7g
7h
7i
32%
7j
none
none
100°C, 5 h
59%
7j
170°C, 15 min
34%
n.c. = no conversion. [a] Substrate concentration 1.0 M. [b] Yield determined
by NMR using an internal standard. [c] Isolated yield.
7j
42%
In contrast, if -ketolactones like 4-hydroxycoumarin (B) are used
as nuclophiles, catalysts of type 7 exhibit much higher activity. At
a concentration of 1.0 M, full conversion of the substrates and
comparably high yields of product 5Ba are obtained with catalyst
1a in presence of an acidic promoter at 100°C (5 h) or at 170°C
(W, 15 min) as well as with catalyst 7j in absence of an acidic
promoter (Scheme 4; Table 2, entries 1, 2, 18). The reaction rate
decreases with higher dilution. At a concentration of 0.25 M, 56%
of the nucleophile B has been converted in presence of catalyst
1a (2 mol-%) and TFA (4 Mol-%) after 15 minutes at 170°C (Table
2, entries 2-4). The latter conditions are applied to compare the
activities of all new complexes 7. Complex 7e exhibits the highest
activity, but no improvement regarding the yield of 5Ba is
7j
27%
7j
none
none
none
none
none
100%
37%
7k
7l
0.25 M
0.25 M
0.25 M
0.25 M
27%
7m
7n
35%
23%
[a] determined by NMR via remained B using an internal standard. [b] 100°C,
5 h. [c] 170°C, 15 min. [d] Isolated yield. [e] Yield determined by NMR using
an internal standard.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
Similar results are obtained with other substrates. In general, high
yields of products 5 are obtained from alcohols 2a-d with 2-keto
lactones if catalyst 1a with an acidic promoter or catalyst 7j are
applied at 170°C (W, 15 min). With 1,3-diketones, however, high
yields are only obtained with catalyst 1a and an acidic promoter
at 100°C (5 h). The yields and diasteroselectivities of the reactions
catalyzed by complex 7j are generally lower, compared to the
same reactions catalyzed by 1a (Scheme 5; Table 3; Figure 2).
Scheme 5. Conversion of terminal tertiary substrates with nucleophiles A-D.
Table 3. Products from alcohols 2a-d with nucleophiles A-D catalyzed by
different catalysts (substrate concentration 1.0 M).
catalyst
1a
nucleophile
products
from 2a
products
from 2b
products
from 2c
products
from 2d
Figure 2. Isolated products from terminal tertiary substrates 2a-d and
nucleophiles A-D.
A
B
5Aa[a,d]
(82%)
5Ab[a,d]
(49%)
5Ac[b,d]
(89%)
5Ad[a,d]
(97%)
It was previously shown, that catalyst 1a converts terminal
secondary propargyl alcohols with various nucleophiles in a
redox-isomerization / Michael addition cascade process (Scheme
1).[4a,4e-f] As expected, the conversion of secondary substrates 2e-
g with nucleophiles A-D in presence of catalyst 1a and TFA as an
acidic promoter proceeds via redox-isomerization product 8 and
leads to the formation of Michael addition products 3 or 4 in most
cases. In contrast, catalyst of type 7 do not catalyze conversions
of secondary alcohols 2e-g, neither in the presence nor in the
absence of an acidic promoter (Scheme 6; Table 4). This is in
accordance with further preliminary examinations regarding the
catalytic activity of complexes 7 towards various terminal
secondary propargyl alcohols.
1a
5Ba[a,d]
(91%)
5Bb[a,d]
(90%,
dr 5:4)
5Bc[b,d]
(54%,
dr 5:2)
5Bd[a,d]
(93%,
dr 5:1)
1a
1a
C
D
5Ca[c,e]
(86%)
5Cb[c,e]
(61%,
dr 15:1)
5Cc[c,e]
(92%,
dr 15:1)
5Cd[c,e]
(98%,
dr 17:1)
5Da[c,e]
(82%)
5Db[f]
(80%,
dr 2:1)
5Dc[f]
(80%,
dr 2:1)
5Dd[c,e]
(98%,
dr 3:1)
7j
7j
A
B
5Aa[a,d]
(19%)
5Ab[a,d]
(8%)
5Ac[a,d]
(15%)
5Ad[a,d]
(15%)
5Ba[a,f]
(89%)
5Bb[a,f]
(67%,
dr 2:1)
5Bc[b,f]
(55%,
dr 1:1)
5Bd[a,f]
(85%,
dr 3:2)
7j
7j
C
D
5Ca[c,f]
(80%)
5Cb[c,f]
(62%,
dr 6:1)
5Cc[c,f]
(81%,
dr 4:1)
5Cd[c,f]
(92%,
dr 2:1)
5Da[c,f]
(39%)
5Dd[c,f]
(90%,
dr 5:2)
[a] Compound previously reported in ref. 4e. [b] Compound previously
reported in ref. 4c. [c] Compound previously reported in ref. 4b. [d] Prepared
by conventional heating (100°C, 5h). [e] 180°C, 5 min. [f] 170°C, 15 min.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
We previously reported, that complex 1a catalyze the
cycloaddition of 1,3-dicarbonyl compounds with some internal
secondary propargyl alcohols. This conversion is especially
interesting with substrates containing an additional alkenyl
substituent like 2h, since the diene product (6Bh) can be further
transformed by a [2+4]-cycloaddition in a one pot process
(Scheme 8).[4e] Byproduct 9Bh is formed with low trans-selectivity
by allylation of the nucleophile and subsequent 5-exo-trig
cyclization.
Scheme 6. Conversion of terminal secondary substrates with nucleophiles A-D.
Table 4. Products of alcohols 2e-g with nucleophiles A-D catalyzed by
catalyst 1a (substrate concentration 1.0 M; 170°C, 15 min).
catalyst
1a
nuc.
A
products
from 2e
products
from 2f
products
from 2g
4Ae[a] (85%)
3Ae[a] (10%)
3Af (68%)
8f[b] (26%)
3Ag (trace)
8g[b] (96%)
Scheme 8. Conversion of alcohol 2h with 4-hydroxycoumarin (B).
1a
B
3Be[a] (64%)
8e[b] (31%)
8f[b] (98%)
8g[b] (99%)
Comparable yields and selectivities are obtained at 100°C (5h) or
at 170°C (W, 15 min) if catalyst 1a (2 mol-%) and TFA (4 mol-%)
are applied. The reaction rate decreases with higher dilution (table
5, entries 1-3). Complexes of type 7 also catalyze this
transformation, but with lower activity and chemoselectivity. The
complexes of type 7 show hardly any differences in activity among
one another (table 5, entries 4-10).
1a
C
3Ce (48%)
8e[b] (46%)
8f[b] (95%)
8g[b] (97%)
1a
D
4De (45%, dr 2:1)
8e[b] (28%)
7a-n
A-D
n.c.
n.c.
n.c.
n.c. = no conversion. [a] Compound previously reported in ref. 4e. [b]
Compound previously reported in ref. 4a.
Table 5. Formation of compounds 6Bh and 9Bh applying different catalysts.
The activation of terminal substrates 2 by complexes of type 1
occurs by the initial formation of alkynyl species I-1 (Scheme 5)
as it was shown by labeling experiments.[4f] We assume, that the
following 1,2-H-shift is initiated by intramolecular protonation of
the alkyne unit via the ligands acidic hydroxyl group. Complexes
of type 7 also activate terminal substrates 2 as alkynyl species (I-
7), but no redox-isomerization takes place, presumably due to the
lower acidity of the ligands amino function (Scheme 7).
No
1[a]
2[b]
3[b]
4[b]
5[b]
6[b]
7[b]
8[b]
9[b]
10[b]
catalyst
1a
promoter
TFA
conc.
1.0 M
1.0 M
0.5 M
0.5 M
0.5 M
0.5 M
0.5 M
0.5 M
0.5 M
1.0 M
6Bh
9Bh
62%[c]
66%[d]
43%[d]
19%[d]
20%[d]
18%[d]
17%[d]
22%[d]
19%[d]
40%[d]
29%[c] (dr 3:2)
24%[d] (dr 3:2)
18%[d] (dr 3:2)
23%[d] (dr 4:3)
23%[d] (dr 2:1)
20%[d] (dr 2:1)
23%[d] (dr 4:3)
15%[d] (dr 2:1)
24%[d] (dr 2:1)
35%[d] (dr 2:1)
1a
TFA
1a
TFA
7c
none
none
none
none
none
none
none
7d
7e
7h
7i
7j
7j
[a] 100°C, 5 h. [b] 170°C, 15 min. [c] Isolated yield. [d] Yield determined by
NMR using an internal standard.
Scheme 7. Activation of terminal propargyl alcohols 2 by complexes 1a or 7j.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
Now, we wanted to apply this transformation to terpenoid-derived
propargyl alcohols 2i-2l. With regard to the synthesis of
phloroglucinol-terpenoid adducts,[7] ploroglucinol derivative E was
used as an additional CH-acidic nucleophile (Scheme 9).
Table 6. Products from internal propargyl alcohols 2h-l with nucleophiles A-
E catalyzed by catalysts 1a or 7j (substrate concentration 1.0 M).
cat.
nuc.
Products
products
products
products
products
from 2h
from 2i
from 2j
from 2k
from 2l
1a
A
6Ah[a,b]
(59%)
9Ah[a,b]
(16%,
6Ai[b]
(18%)
dec.
dec.
10k[b]
(24%)
dec.
dr 6:1)
1a
1a
1a
B
C
E
6Bh[a,c]
(66%)
9Bh[a,c]
(24%,
6Bi
(trace)
6Bk
(trace)
6Bl
(trace)
dr 3:2)
6Ch[c]
(60%)
9Ch[c]
(24%,
dr 2:1)
6Ci[c]
(13%)
6Cj
(trace)
6Ck[c]
(19%,
dr 3:2)
6Cl
(trace)
10l[c]
(5%)
6Eh[c]
(30%)
9Eh[c]
(17%,
dr 2:1)
6Ei[c]
(10%)
dec.
6Ek[c]
(12%)
dec.
7j
7j
A
B
6Ah[a,b]
(28%)
n.c.
n.c.
n.c.
n.c.
Scheme 9. Conversion of internal secondary substrates with nucleophiles A-E.
6Bh[a,c]
(40%)
9Bh[a,c]
(35%,
6Bi[c]
(50%)
6Bj[c]
(17%)
6Bk[c]
(55%,
dr 2:1)
10k[c]
(9%)
6Bl[c]
(61%,
dr 3:1)
10l[c]
Unfortunately, we found the substrate scope of the original
procedure to be very limited. Conversions of terpene derivatives
2i-l with nucleophiles A-E applying catalyst 1a (2 mol-%) and TFA
(4 mol-%) lead to extensive decomposition and only small
amounts of dihydropyranes 6 are isolated. In contrast, propargyl
alcohols 2i, 2k and 2l are converted in moderate to good yields
with nucleophiles B, C or E if catalyst 7j without an acidic
promoter is applied. Only small quantities of products 6 are
obtained from alcohol 2j. Conversions of internal secondary
propargyl alcohols 2i-l with 1,3-dione A are not catalyzed by
dr 2:1)
(6%)
7j
7j
7j
C
D
E
6Ch[c]
(42%)
9Ch[c]
(19%,
dr 2:1)
6Ci[c]
(44%)
6Cj[c]
(15 %)
6Ck[c]
(68%,
dr 2:1)
10k[c]
(5%)
6Cl[c]
(75%,
dr 2:1)
10l[c]
(3%)
dec.
dec.
dec.
n.c.
6Dk[c]
(13%,
dr 5:2)
10k[c]
(4%)
dec.
complex 7j, whereas nucleophile
D leads to extensive
decomposition. Occasionally, small amounts of the oxidized
byproducts 10 are isolated. Uncyclized products 11 are formed
from nucleophile E in some cases (Table 6; Figure 3).
6Eh[c]
(35%)
9Eh[c]
(43%,
dr 3:2)
11Eh[c]
(18%)
6Ei[c]
(33%)
6Ek[c]
(42%,
dr 5:4)
11El[c]
(56%,
dr 1:1)
n.c. = no conversion. dec. = decomposition. [a] Compound previously
reported in ref. 4e. [b] Prepared by conventional heating (100°C, 5h). [c]
170°C, 15 min.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
Conclusions
In principle, triaminocyclopentadienyl ruthenium complexes (7)
are useful catalysts for cascade conversions of propargyl alcohols.
Their synthesis is straightforward and enantiopure derivatives for
future applications in asymmetric catalysis are easily accessible.
However, the simpler diaminocyclopentadienone catalyst 1a is
superior to complexes of type 7 in terms of converting terminal
tertiary substrates. Moreover, redox-isomerization processes of
terminal secondary derivatives are not catalyzed at all by the new
complexes (7). In contrast, introducing the third amine-function on
the cyclopentadienyl ligand has a significant effect on the
conversion of internal substrates. The new catalysts (7) extend
the scope of cascade conversions of internal 1-alkenylpropargyl
alcohols, originally catalyzed by ruthenium catalyst 1a, to various
terpenoid-derived derivatives. In addition, reactions catalyzed by
complexes of type 7 are applicable for the conversion of acid-
sensitive substrates, since they do not require an acidic promoter.
A broad range of terpenoid and phloroglucinol adducts are
accessible by complementary application of both types of
catalysts. The compounds obtained are suitable as structural
building blocks for the synthesis of related bioactive natural
products and analogues. Further applications of the new catalysts,
especially in the context of asymmetric catalysis is the subject of
our ongoing research.
Experimental Section
See the Supporting Information for full experimental procedures and
characterization data of all products.
General Information
All reactions were carried out in a dry atmosphere under argon. The
chemicals used were dried and purified according to common procedures.
Products were identified by spectroscopic analysis (1H NMR, 13C NMR,
IR, MS, HRMS). Multiplicity was determined by DEPT spectra for all
compounds. Infrared spectra were obtained with a PERKIN-ELMER FT-IR
2000 or a VERTEX 70V. NMR spectra were recorded on a BRUKER DPX
400 or a BRUKER AVANCE 600 spectrometer. MS data was obtained with
a FINNIGAN SSQ 7000 (EI) or a WATERS ACQUITY UPLC-MS H-CLASS
(ESI) and HRMS data was obtained on a FINNIGAN MAT 95. Specific
optical rotation of chiral compounds was measured on an ANTON PAAR
MCP 150 polarimeter. Reactions using microwave irradiation were
performed in an ANTON PAAR MONOWAVE 300 reactor.
General procedure for the preparation of catalysts 7: Ru3(CO)12 (0.34
eq.) and 1 eq. of the respective ligand L7 were dissolved in toluene (0.1
M). The solution was stirred at 100°C for 5 h. Evaporation of the solvent
and rapid flash chromatography on oven dried silica (CH2Cl2 / CH3OH;
100:0, 99.5:0.5, 98:2) furnished the purified products as yellow foams.
1
7b (C28H28N3O3RuBF4): H NMR (600 MHz, CDCl3):  = 8.13 (br, d , J =
7.2 Hz, 2H), 7.50-7.45 (m, 4H), 7.42 (br, t, J = 7.4 Hz, 2H), 7.32 (br, d, J =
7.5 Hz, 2H), 3.61 (dd, J = 6.8, 3.7 Hz, 1H), 3.58 (dd, J = 6.6, 3.9 Hz, 1H),
2.65 (dd, J = 6.6, 4.0 Hz, 1H), 2.62 (dd, J = 6.9, 3.6 Hz, 1H), 2.48-2.46 (m,
4H), 2.00 (s, 6H), 1.42-1.40 ppm (m, 4H); 13C NMR (150 MHz, CDCl3):  =
193.8 (br, 3 C), 141.0 (C), 135.8 (br, 2 CH), 133.7 (br, 2 CH), 130.9 (2 C),
129.8 (2 CH), 129.1 (br, 2 CH), 129.0 (br, 2 CH), 120.1 (2 C), 69.7 (2 C),
Figure 3. Isolated products from internal secondary substrates 2h-l and
nucleophiles A-E.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
53.3 (2 CH2), 50.3 (2 CH2), 43.7 (2 CH3), 25.0 (2 CH2); IR (KBr)  = 3058
(w), 2955 (w), 2927 (w), 2875 (w), 2060 (s), 2018 (s), 2000 (s), 1519 (m),
1549 (m), 1455 (m), 1417 (m), 1365 (m), 1348 (m), 1318 (m), 1083 (s),
1057 (s), 726 (m), 705 cm-1 (m); MS (EI): m/z (%): 557 (18), 556 [M-BF4]+
(20), 531 (46), 529 (100), 528 [M-CO,-BF4]+ (62), 527 (55), 526 (40), 501
(65), 500 (45), 499 (99), 498 (54), 497 (51), 496 (40), 471 (80), 470 (63),
469 (90), 468 (75), 467 (58), 466 (40); HRMS (EI): m/z calcd for
C27H28N3O2Ru: 528.1220 [M-CO,-BF4]+; found: 528.1224.
3057 (w), 2923 (w), 2860 (w), 2809 (w), 1986 (m), 1498 (m), 1048 (m), 730
(m), 698 cm-1 (w); MS (ESI): m/z (%): 657 [M-BF4]+ (16), 656 (23), 632 (20),
631 (54), 630 (35), 629 [M-CO,-BF4]+ (100), 628 (57), 627 (45), 626 (35),
471 (36); HRMS (EI): m/z calcd for C34H31N4O2Ru: 629.1486 [M-CO,-
BF4]+; found: 629.1505.
7g (C34H31N4O3RuBF4): 1H NMR (600 MHz, CDCl3):  = 9.20 (s, 1H), 7.80-
7.34 (m, 11H), 7.10 (d, J = 7.8 Hz, 1H), 7.06 (t, J = 7.5 Hz, 1H), 6.91 (t, J
= 7.4 Hz, 1H), 6.39 (d, J = 2.1 Hz, 1H), 3.48 (t, J = 5.0 Hz, 1H), 3.46 (dd, J
= 6.4, 3.4 Hz, 1H), 3.43 (dd, J = 6.4, 3.8 Hz, 1H), 2.57 (dd, J = 6.9, 4.0 Hz,
1H), 2.55 (dd, J = 6.5, 3.7 Hz, 1H), 2.48-2.42 (m, 4H), 2.07 ppm (s, 6H);
13C NMR (150 MHz, CDCl3):  = 192.6 (3 C), 141.0 (C), 136.6 (C), 135.0-
133.5 (br, 2 CH), 132.2-130.8 (br, 2 CH), 130.4 (2 CH), 129.8 (br, 4 CH),
127.4 (br, 2 C), 126.0 (C), 123.5 (CH), 121.6 (CH), 118.8 (CH), 118.0 (2
C), 117.4 (CH), 112.1 (CH), 107.9 (C), 68.2 (2 C), 49.8 (2 CH2), 44.2 (CH2),
41.5 (2 CH3), 24.0 ppm (CH2); IR (ATR)  = 3382 (w), 3318 (w), 3054 (w),
2922 (w), 2859 (w), 2812 (w), 1996 (m), 1569 (m), 1525 (m), 1358 (m),
1049 (s), 738 (m), 697 cm-1 (m); MS (ESI): m/z (%): 645 [M-BF4]+ (20), 619
(20), 617 [M-CO,-BF4]+ (36), 616 (21), 460 (37), 459 (100); HRMS (EI): m/z
calcd for C33H31N4O2Ru: 617.1486 [M-CO,-BF4]+; found: 617.1510.
7c (C31H28N3O3RuBF4): 1H NMR (600 MHz, CDCl3):  = 7.90-7.29 (m, 10H),
7.10-7.09 (m, 3H), 6.75-6.73 (m, 2H), 3.66 (t, J = 5.7 Hz, 1H), 3.54 (dd, J
= 6.7, 3.7 Hz, 1H), 3.51 (dd, J = 6.6, 3.8 Hz, 1H), 3.48 (d, J = 5.7 Hz, 2H),
2.68 (dd, J = 6.6, 3.9 Hz, 1H), 2.65 (dd, J = 6.6, 3.8 Hz, 1H), 2.10 ppm (s,
6H); 13C NMR (150 MHz, CDCl3):  = 192.8 (3 C), 140.2 (C), 135.3 (C),
135.2-133.8 (br, 2 CH), 133.0-131.2 (br, 2 CH), 130.1 (2 CH), 129.6 (br, 4
CH), 128.6 (2 CH), 127.8 (CH), 127.6 (br, 2 C), 126.9 (2 CH), 118.4 (2 C),
65.5 (2 C), 49.8 (2 CH2), 49.1 (CH2), 41.4 ppm (2 CH3); IR (ATR)  = 3339
(w), 3059 (w), 2950 (w), 2924 (w), 2861 (w), 1728 (m), 1568 (m), 1452 (m),
1275 (m), 1121 (m), 1055 (s), 741 (m), 697 cm-1 (m); MS (EI): m/z (%): 592
[M-BF4]+ (16), 591 (10), 566 (30), 565 (18), 564 [M-CO,-BF4]+ (57), 563
(33), 562 (25), 561 (21), 408 (23), 407 (32), 406 (100); HRMS (EI): m/z
calcd for C30H28N3O2Ru: 564.1221 [M-CO,-BF4]+; found: 564.1236.
7h (C29H26N3O4RuBF4): 1H NMR (600 MHz, CDCl3):  = 8.00-7.44 (m, 10H),
7.19 (dd, J = 1.8, 0.6 Hz, 1H), 6.17 (dd, J = 1.8, 3.2 Hz, 1H), 5.88 (dd, J =
3.2, 0.6 Hz, 1H), 3.70 (t, J = 5.7 Hz, 1H), 3.61 (dd, J = 6.6, 3.5 Hz, 1H),
3.58 (dd, J = 6.5, 3.8 Hz, 1H), 3.49 (d, J = 5.7 Hz, 2H), 2.71 (dd, J = 6.5,
3.8 Hz, 1H), 2.68 (dd, J = 6.6, 3.6 Hz, 1H), 2.16 ppm (s, 6H); 13C NMR
(150 MHz, CDCl3):  = 192.8 (3 C), 147.8 (C), 142.9 (CH), 139.9 (C), 135.2-
133.9 (br, 2 CH), 133.2-131.8 (br, 2 CH), 130.4 (2 CH), 130.0 (br, 4 CH),
127.7 (br, 2 C), 118.5 (2 C), 110.6 (CH), 109.0 (CH), 68.6 (2 C), 50.1 (2
CH2), 41.8 (CH2), 41.6 ppm (2 CH3); IR (ATR)  = 3342 (w), 3057 (w), 2929
(w), 2870 (w), 1597 (m), 1567 (s), 1505 (m), 1444 (m), 1412 (m), 1365 (m),
1336 (m), 1285 (m), 1245 (m), 1051 (s), 1030 (s), 1020 (s), 953 (m), 913
(m), 728 (s), 703 cm-1 (s); MS (ESI): m/z (%): 582 [M-BF4]+ (15), 557 (12),
556 (49), 555 (24), 554 [M-CO,-BF4]+ (100), 553 (50), 552 (39), 332 (24),
317 (31), 316 (72), 315 (21), 314 (53); HRMS (EI): m/z calcd for
C28H26N3O3Ru: 554.1012 [M-CO,-BF4]+; found: 554.1021.
7d (C32H30N3O3RuBF4): 1H NMR (600 MHz, CDCl3):  = 7.88-7.29 (m, 10H),
7.12-7.05 (m, 3H), 6.60 (d, J = 7.0 Hz, 2H), 3.53 (dd, J = 6.6, 3.6 Hz, 1H),
3.50 (dd, J = 6.5, 3.7 Hz, 1H), 3.21 (s, 1H), 2.67 (dd, J = 6.6, 3.8 Hz, 1H),
2.64 (dd, J = 6.5, 3.6 Hz, 1H), 2.48 (t, J = 6.7 Hz, 2H), 2.32 (t, J = 6.7 Hz,
2H), 2.11 ppm (s, 6H); 13C NMR (150 MHz, CDCl3):  = 192.6 (3 C), 140.8
(C), 136.1 (C), 135.4-133.6 (br, 2 CH), 132.2-131.1 (br, 2 CH), 130.0 (2
CH), 129.7 (br, 4 CH), 128.6 (2 CH), 128.1 (2 CH), 127.6 (br, 2 C), 126.6
(CH), 118.0 (2 C), 68.0 (2 C), 49.7 (2 CH2), 45.6 (CH2), 41.3 (2 CH3), 34.2
ppm (CH2); IR (ATR)  = 3362 (w), 3059 (w), 2926 (w), 2859 (w), 1990 (m),
1044 (m), 695 cm-1 (m); MS (EI): m/z (%): 579 (28), 578 [M-CO,-BF4]+ (16),
523 (21), 522 (37), 521 (32), 520 (33), 519 (24), 480 (22), 479 (36), 478
(21), 446 (29), 332 (35), 316 (100); MS (ESI): m/z (%): 598 (25), 580 (33),
579 (60), 578 [M-CO,-BF4]+ (35), 577 (36), 576 (28), 575 (22), 538 (33),
537 (45), 536 (82), 354 (53), 282 (29), 171 (33); HRMS (EI): m/z calcd for
C31H30N3O2Ru: 578.1377 [M-CO,-BF4]+; found: 578.1384.
7i (C28H30N3O4RuBF4): 1H NMR (400 MHz, CDCl3):  = 8.00-7.30 (m, 10H),
4.51 (t, J = 5.5 Hz, 1H), 3.54 (dd, J = 6.7, 3.6 Hz, 1H), 3.50 (dd, J = 6.5,
3.9 Hz, 1H), 3.20 (td, J = 5.1, 4.7 Hz, 2H), 2.68 (dd, J = 6.4, 3.8 Hz, 1H),
2.63 (dd, J = 6.6, 3.6 Hz, 1H), 2.28 (td, J = 6.2, 5.9 Hz, 2H), 2.09 (s, 6H),
2.01 (t, J = 4.5 Hz, 1H), 1.14 ppm (m, 4H); 13C NMR (100 MHz, CDCl3): 
= 193.1 (3 C), 143.4 (C), 135.7-134.0 (br, 2 CH), 133.3-131.3 (br, 2 CH),
130.1 (2 CH), 129.7 (br, 4 CH), 128.2 (2 C), 118.3 (2 C), 67.7 (2 C), 61.2
(CH2), 50.0 (2 CH2), 45.1 (CH2), 41.7 (2 CH3), 28.8 (CH2), 25.2 ppm (CH2);
IR (ATR)  = 3546 (w), 3348 (w), 2930 (w), 2874 (w), 2070 (s), 1991 (s),
1540 (s), 1503 (m),1444 (m), 1416 (m), 1364 (m), 1271 (m), 1199 (w),
1050 (s), 1030 (s), 951 (m), 753 (m), 724 (m), 702 cm-1 (m); MS (ESI): m/z
(%): 549 (18), 548 (50), 547 (27), 546 [M-CO,-BF4]+ (100), 545 (53), 544
(42), 543 (30), 540 (18); HRMS (ESI): m/z calcd for C27H30N3O3Ru:
546.1325 [M-CO,-BF4]+; found: 546.1349.
7e (C27H25N4O3RuBF4): 1H NMR (400 MHz, CDCl3):  = 7.81-7.75 (m, 3H),
7.48-7.38 (m, 7H), 3.76 (t, J = 6.4 Hz, 1H), 3.19 (dd, J = 7.0, 4.2 Hz, 1H),
3.14 (dd, J = 6.8, 4.5 Hz, 1H), 2.95 (q, J = 6.7 Hz, 2H), 2.42 (dd, J = 6.7,
4.6 Hz, 1H), 2.38 (dd, J = 7.0, 4.2 Hz, 1H), 2.04 (s, 6H), 1.96 ppm (t, J =
6.8 Hz, 2H); 13C NMR (100 MHz, CDCl3):  = 199.9 (3 C), 136.8 (C), 135.2-
131.8 (br, 4 CH), 130.3 (2 C), 129.4 (br, 4 CH), 129.3 (2 CH), 117.5 (C),
111.6 (2 C), 67.9 (2 C), 49.8 (2 CH2), 43.2 (2 CH3), 40.2 (CH2), 19.6 ppm
(CH2); IR (ATR)  = 3343 (w), 2921 (w), 2861 (w), 2247 (w), 1993 (m),
1932 (m), 1499 (m), 1108 (w), 1063 (w), 1020 (w), 932 (w), 862 (w), 792
(w), 740 (w), 696 cm-1 (w); MS (EI): m/z (%): 508 (16), 506 (22), 384 (29),
383 (100), 369 (15), 328 (22), 327 (19); MS (ESI): m/z (%): 527 [M-CO,-
BF4]+ (100), 526 (68), 525 (56), 524 (38), 371 (23), 369 (42), 354 (22);
HRMS (EI): m/z calcd for C26H25N4O2Ru: 527.1016 [M-CO,-BF4]+; found:
527.1028.
7j (C29H30N3O4RuBF4): 1H NMR (600 MHz, CDCl3): 1H NMR (600 MHz,
CDCl3): = 8.00-7.35 (m, 10H), 3.82 (t, J = 5.4 Hz, 1H), 3.60-3.56 (m, 2H,
H6), 3.51 (ddd, J = 13.8, 6.9, 3.4 Hz, 1H), 3.44 (dt, J = 8.3, 7.0 Hz, 1H),
3.37 (dt, J = 8.2, 6.5 Hz, 1H), 2.73-2.68 (m, 2H), 2.34 (ddd, J = 12.9, 5.6,
3.5 Hz, 1H), 2.17 (s, 3H), 2.16 (s, 3H), 2.13 (ddd, J = 12.7, 7.0, 5.3 Hz,
1H), 1.66-1.51 (m, 3H), 1.09-1.03 ppm (m, 1H); 13C NMR (150 MHz,
CDCl3): = 192.9 (3 C), 140.9 (C), 135.8-130.8 (br, 4 CH), 130.2 (CH),
130.1 (CH), 129.8 (br, 4 CH), 127.9 (C), 127.8 (C), 118.8 (C), 118.0 (C),
75.3 (CH), 68.5 (C), 68.3 (C), 68.1 (CH2), 50.0 (CH2), 49.9 (CH2), 48.5
(CH2), 41.6 (CH3), 41.4 (CH3), 28.3 (CH2), 25.5 ppm (CH2); IR (ATR)  =
3360 (w), 2963 (w), 2874 (w), 2070 (m), 1990 (m), 1529 (m), 1499 (m),
1444 (m), 1417 (m), 1364 (m), 1060 (m), 1048 (s), 1033 (s), 949 (m), 755
7f (C35H31N4O3RuBF4): 1H NMR (400 MHz, CDCl3): 1H NMR (400 MHz,
CDCl3):  = 7.90-7.41 (m, 10H), 7.27-7.25 (m, 2H), 7.08-7.05 (m, 1H), 6.88-
6.85 (m, 1H), 6.24 (t, J = 2.1 Hz, 2H), 6.12 (t, J = 2.1 Hz, 2H), 3.63 (dd, J
= 6.8, 3.6 Hz, 1H), 3.59 (dd, J = 6.5, 3.9 Hz, 1H), 3.45 (d, J = 6.0 Hz, 2H),
3.32 (t, J = 6.0 Hz, 1H), 2.67 (dd, J = 6.7, 4.0 Hz, 1H), 2.64 (dd, J = 6.6,
3.9 Hz, 1H), 2.13 ppm (s, 6H); 13C NMR (100 MHz, CDCl3):  = 193.3 (3
C), 140.6 (C), 139.5 (C), 135.5-134.3 (br, 2 CH), 133.1-132.0 (br, 2 CH),
131.2 (C), 130.3 (CH), 129.9 (2 CH), 129.0 (br, 4 CH), 128.5 (br, 2 CH),
127.9 (br, 2 C), 127.7 (CH), 121.5 (2 CH), 119.0 (2 C), 109.9 (2 CH), 68.8
(2 C), 50.1 (2 CH2), 45.7 (CH2), 41.5 ppm (2 CH3); IR (ATR)  = 3341 (w),
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
(m), 702 cm-1 (m); MS (ESI): m/z (%): 586 [M-BF4]+ (25), 561 (18), 560
(53), 559 (29), 558 [M-CO,-BF4]+ (100), 557 (58), 556 (44), 400 (40), 385
(20), 328 (45), 316 (51), 315 (31), 314 (100); HRMS (EI): m/z calcd for
C28H30N3O3Ru: 558.1326 [M-CO,-BF4]+; found: 558.1343; []D20 for (R)-7j
= -17.8° (c = 0.40, CH2Cl2); []D20 for (S)-7j = +21.8° (c = 0.40, CH2Cl2).
(w), 3307 (m), 2974 (w), 2922 (w), 2862 (w), 1569 (m), 1526 (m), 1456 (m),
1443 (m), 1414 (m), 1362 (m), 1277 (m), 1104 (m), 1057 (m), 1007 (s),
911 (m), 743 (m), 732 (m), 703 cm-1 (m); MS (EI): m/z (%): 703 [M-BF4]+
(10), 675 [M-CO,-BF4]+ (15), 333 (30), 332 (89), 317 (26), 316 (82), 314
(28), 313 (20), 228 (36), 227 (100); HRMS (EI): m/z calcd for
C35H33N4O4Ru: 675.1540 [M-CO,-BF4]+; found: 675.1539; []D20 for (S)-3n
= -20.0° (c = 0.25, CH2Cl2).
7k (C32H30N3O3RuBF4): 1H NMR (400 MHz, CDCl3):  = 8.10-7.35 (m, 10H),
7.15-7.12 (m, 3H), 6.58-6.53 (m, 2H), 3.91 (dq, J = 8.3, 6.9 Hz, 1H), 3.65
(d, J = 8.6 Hz, 1H), 3.64-3.52 (m, 2H), 2.75-2.62 (m, 2H), 2.19 (s, 3H), 2.03
(s, 3H), 1.00 ppm (d, J = 6.8 Hz, 3H); 13C NMR (100 MHz, CDCl3):  =
193.0 (3 C), 141.5 (C), 141.0 (C), 135.4-134.2 (br, 2 CH), 132.7-131.6 (br,
2 CH), 130.5 (CH), 130.2 (br, 2 CH), 130.1 (CH), 129.4 (br, 2 CH), 128.7
(2 CH), 127.8 (C), 127.7 (C), 127.5 (CH), 124.9 (2 CH), 120.2 (C), 117.3
(C), 68.1 (C), 67.6 (C), 53.4 (CH), 50.1 (CH2), 49.8 (CH2), 41.8 (CH3), 41.5
(CH3), 23.9 ppm (CH3); IR (ATR)  = 3372 (w), 3057 (w), 2958 (w), 2924
(w), 2864 (w), 1532 (m), 1502 (m), 1362 (m), 1044 (s), 695 (m), 648 cm-1
(m); MS (ESI): m/z (%): 578 [M-CO,-BF4]+ (98), 577 (58), 576 (47), 575
(37), 505 (21), 504 (67), 420 (23), 372 (22), 371 (28), 354 (47); HRMS (EI):
m/z calcd for C31H30N3O2Ru: 578.1377 [M-CO,-BF4]+; found: 578.1404;
[]D20 for (R)-7k = +64.5° (c = 0.33, CH2Cl2).
Acknowledgements
This work was supported by the German Research Foundation
DFG (No. 265182801).
Keywords: cyclopentadienyl ligands • heterocycles •
homogeneous catalysis • ruthenium • terpenoids
[1]
a) Y. Wang, H. Lu, P. F. Xu, Acc. Chem. Res. 2015, 48, 1832-1844; b)
Y. Wang, L. Zhang, P. Lu, H. Gao, J. Zhang, P.-F. Xu, H. Wei in Catalytic
Cascade Reactions (Eds.: P.-F. Xu, W. Wang), John Wiley & Sons,
Hoboken, 2014, pp. 145-331; c) E.-I. Negishi, G. Wang, G. Zhu, P. von
Zezschwitz, A. De Meijere, N. T. Patil, Y. Yamamoto, G. Balme, D.
Bouyssi, N. Monteiro, T. J. J. Müller, J. Pérez-Castells, C. Aubert, L.
Fensterbank, V. Gandon, M. Malacria, C. Bruneau, S. Dérien, P. H.
Dixneuf in Metal Catalyzed Cascade Reactions (Ed.: T. J. J. Müller),
Springer, Berlin, 2006, pp. 1-340; d) L. F. Tietze, B. Brasche, K. Gericke
in Domino Reactions in Organic Synthesis, Wiley-VCH, Weinheim, 2006,
pp. 359-493;
7l (C30H30N3O7RuBF4): 1H NMR (600 MHz, CDCl3):  = 8.20-7.40 (m, 10H),
4.66 (d, J = 9.4 Hz, 1H), 3.64-3.55 (m, 2H), 3.57 (s, 3H), 3.49 (dt, J = 9.3,
4.4 Hz, 1H), 3.45 (s, 3H), 2.72-2.66 (m, 2H), 2.37 (dd, J = 17.4, 4.2 Hz,
1H), 2.28 (d, J = 17.4, 4.6 Hz, 1H), 2.23 (s, 3H), 2.09 ppm (s, 3H); 13C
NMR (150 MHz, CDCl3):  = 192.9 (3 C), 170.6 (C), 169.7 (C), 140.3 (C),
135.2-134.6 (br, 2 CH), 132.6-131.9 (br, 2 CH), 130.5 (CH), 130.4 (CH),
129.9 (br, 4 CH), 128.3 (C), 127.1 (C), 120.5 (C), 117.1 (C), 69.6 (C), 67.6
(C), 53.0 (CH), 52.2 (CH3), 52.1 (CH3), 50.2 (CH2), 49.7 (CH2), 41.8 (CH3),
41.4 (CH3), 35.9 ppm (CH2); IR (ATR)  = 3396 (w), 3056 (w), 2992 (w),
2953 (w), 1742 (m), 1598 (m), 1564 (s), 1514 (m), 1457 (m), 1443 (m),
1412 (m), 1364 (m), 1240 (m), 1208 (m), 1052 (s), 1025 (s), 954 (m), 916
(m), 731 (m), 705 cm-1 (m); MS (EI): m/z (%): 618 [M-CO,-BF4]+ (10), 597
(18), 462 (22), 461 (81), 460 (45), 459 (100), 441 (30), 442 (67), 443 (70);
HRMS (EI): m/z calcd for C29H30N3O6Ru: 618.1173 [M-CO,-BF4]+; found:
618.1173; []D20 for (S)-7l = -13.0° (c = 0.20, CH2Cl2).
[2]
a) R. Ardkhean, D. F. J. Caputo, S. M. Morrow, H. Shi, Y. Xiong, E. A.
Anderson, Chem. Soc. Rev. 2016, 45, 1557-1569; b) C. I. Stathakis, P.
L. Gkizis, A. L. Zografos, Nat. Prod. Rep. 2016, 33, 1093-1117; c) A. C.
Jones, J. A. May, R. Sarpong, B. M. Stoltz, Angew. Chem. 2014, 126,
2590-2628; Angew. Chem. Int. Ed. 2014, 53, 2556-2591; d) K. Kumar in
Concepts and Case Studies in Chemical Biology (Eds.: H. Waldmann, P.
Janning), Wiley-VCH, Weinheim, 2014, pp. 391-414; e) K. C. Nicolaou,
D. J. Edmonds, P. B. Bulger, Angew. Chem. 2006, 118, 7292-7344;
Angew. Chem. Int. Ed. 2006, 43, 7134-7186.
7m (C31H32N3O7RuBF4): 1H NMR (600 MHz, CDCl3):  = 8.14-7.30 (m,
10H), 4.38 (d, J = 8.7 Hz, 1H), 3.68-3.61 (m, 2H), 3.54 (s, 3H), 3.53 (s, 3H),
3.40 (dt, J = 8.2, 6.5 Hz, 1H), 2.71-2.65 (m, 2H), 2.22 (s, 3H), 2.11 (s, 3H),
1.95 (t, J = 7,0 Hz, 2H), 1.56-1.45 ppm (m, 2H); 13C NMR (150 MHz,
CDCl3):  = 193.2 (3 C), 173.0 (C), 170.8 (C), 140.3 (C), 135.5-134.8 (br,
2 CH), 133.2-132.2 (br, 2 CH), 130.5 (CH), 130.4 (CH), 130.0 (2 CH), 129.9
(br, 2 CH), 128.3 (C), 127.3 (C), 119.7 (C), 118.7 (C), 70.0 (C), 68.0 (C),
55.6 (CH), 52.8 (CH3), 52.0 (CH3), 50.2 (CH2), 49.9 (CH2), 41.7 (CH3), 41.6
(CH3), 29.4 (CH2), 27.3 ppm (CH2); IR (ATR)  = 3360 (w), 3018 (w),
2952(w), 2075 (s), 1994 (s), 1735 (s), 1537 (s), 1501 (m), 1442 (m), 1417
(m), 1364 (m), 1268 (w), 1205 (m), 1048 (s), 755 (m), 703 cm-1 (m); MS
(ESI): m/z (%): 635 (17), 634 (52), 633 (30), 632 [M-CO,-BF4]+ (100), 631
(55), 630 (47), 629 (40), 626 (15); HRMS (ESI): m/z calcd for
C30H32N3O6Ru: 632.1329 [M-CO,-BF4]+; found: 632.1339; []D20 for (S)-7m
= -12.3° (c = 0.30, CH2Cl2).
[3]
a) E. Haak, Eur. J. Org. Chem. 2017, 940–949; b) Y. Hu, M. Bai, Y. Yang,
Q. Zhou, Org. Chem. Front. 2017, 4, 2256-2275; c) A. L. S. Kumari, A.
S. Reddy, K. C. K. Swamy, Org. Biomol. Chem. 2016, 14, 6651-6671; d)
J.-P. Genêt, P. Y. Toullec, V. Michelet in Modern Alkyne Chemistry (Eds.:
B. M. Trost, C.-J. Li), Wiley-VCH, Weinheim, 2014, pp. 27-68; e) I. D. G.
Watson, F. D. Toste, Chem. Sci. 2012, 3, 2899-2919; f) P. Pérez-Galán,
V. López-Carillo, A. M. Echavarren, Contrib. Sci. 2010, 6, 143-153; g) E.
Jiménez-Núñez, A. M. Echavarren, Chem. Rev. 2008, 108, 3326-3350;
h) V. Michelet, P. Y. Toullec, J.-P. Genêt, Angew. Chem. 2008, 120,
4338-4386; Angew. Chem. Int. Ed. 2008, 47, 4268-4315; i) L. Zhang, J.
Sun, S. A. Kozmin, Adv. Synth. Catal. 2006, 348, 2271-2296; j) C.
Bruneau, S. Dérien, P. H. Dixneuf, Top. Organomet. Chem. 2006, 19,
295-326.
[4]
a) J. Kaufmann, E. Jäckel, E. Haak, Angew. Chem. 2018, 130, 6010-
6014; Angew. Chem. Int. Ed. 2018, 57, 5908-5911; b) E. Jäckel, J.
Kaufmann, E. Haak, Synthesis 2018, 50, 742-752; c) N. Thies, E. Haak,
Angew. Chem. 2015, 127, 4170-4174; Angew. Chem. Int. Ed. 2015, 54,
4097-4101; d) N. Thies, M. Gerlach, E. Haak, Eur. J. Org. Chem. 2013,
7354-7365; e) A. Jonek, S. Berger, E. Haak, Chem. Eur. J. 2012, 18,
15504-15511; f) N. Thies, C. G. Hrib, E. Haak, Chem. Eur. J. 2012, 18,
6302-6308.
7n (C36H33N4O5RuBF4): 1H NMR (600 MHz, CDCl3+CD3OD): = 7.54-7.33
(m, 10H), 7.32 (d, J = 8.2 Hz, 1H), 7.12 (t, J = 7.5 Hz, 1H), 7.01 (d, J = 7.9
Hz, 1H), 6.96 (t, J = 7.4 Hz, 1H), 6.54 (s, 1H), 3.58 (br t, J = 6.0 Hz, 1H),
3.52 (s, 3H), 3.51-3.46 (m, 2H), 2.75 (dd, J = 15.2, 5.7 Hz, 1H), 2.73 (dd,
J = 15.2, 6.4 Hz, 1H), 2.64-2.60 (m, 2H), 2.12 (s, 3H), 2.07 ppm (s, 3H);
13C NMR (150 MHz, CDCl3+CD3OD):  = 192.3 (3 C), 170.8 (C), 140.8 (C),
136.2 (C), 135.0-134.4 (br, 2 CH), 131.4-131.0 (br, 2 CH), 130.5 (CH),
130.4 (CH), 130.0-129.6 (br, 4 CH), 127.3 (C), 127.0 (C), 126.4 (C), 123.6
(CH), 121.8 (CH), 119.9 (br, C), 119.1 (CH), 118.1 (br, C), 117.4 (CH),
111.7 (CH), 106.1 (C), 68.5 (C), 67.9 (C), 55.3 (CH), 52.5 (CH3), 49.8 (CH2),
49.7 (CH2), 41.5 (CH3), 41.4 (CH3), 27.9 ppm (CH2); IR (ATR)  = 3362
[5]
[6]
R. Gompper, H. Glöckner, Angew. Chem. 1984, 96, 48–49.
a) E. Haak, Eur. J. Org. Chem. 2008, 788-792; b) E. Haak, Eur. J. Org.
Chem. 2007, 2815-2824.
[7]
a) X.-W. Yang, R. B. Grossman, G. Xu, Chem. Rev. 2018, 118, 3508-
3558; b) J.-A. Richard, R. H. Puower, D. Y.-K. Chen, Angew. Chem. 2012,
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
124, 4612-4638; Angew. Chem. Int. Ed. 2012, 51, 4536-4561; c) I. P.
Singh, J. Sidana, S. B. Bharate, W. J. Foley, Nat. Prod. Rep. 2010, 27,
393-416; d) I. P. Singh, S. B. Bharate, Nat. Prod. Rep. 2006, 23, 558-
591.
This article is protected by copyright. All rights reserved.

10.1002/chem.202102959
Chemistry - A European Journal
FULL PAPER
Entry for the Table of Contents
FULL PAPER
J. Hatzfeld, S. Skowaisa, E. Jäckel, J.
Kaufmann, E. Haak*
Page No. – Page No.
Triaminocyclopentadienyl Ruthenium
Complexes – New Catalysts for
Cascade Conversions of Propargyl
Alcohols
Triaminocyclopentadienyl ruthenium complexes are useful catalysts for cascade
conversions of propargyl alcohols with CH-acidic nucleophiles. Their catalytic
activities complement the activities of known diaminocyclopentadienone ruthenium
complexes. A wide range of cyclic terpenoid and phloroglucinol adducts are obtained
by complementary application of both types of catalysts.
This article is protected by copyright. All rights reserved.