Aminocarbonylation (hydrazinocarbonylation) of iodoalkenes and iodoarenes

Article abstract of DOI:10.1016/j.tet.2016.12.063

Iodoalkenes such as 1-iodocyclohexene, 4-tert-butyl-1-iodocyclohexene, α-iodostyrene and 17-iodoandrost-16-ene were aminocarbonylated in palladium-catalysed reaction using 1,1-disubstituted (cyclic) hydrazines (3-amino-3-azabicyclo[3.3.0]octane and (S)-1-amino-2-methoxymethylpyrrolidine (SAMP)/(R)-1-amino-2-methoxymethyl-pyrrolidine (RAMP)) as N-nucleophiles. The corresponding hydrazides were formed in moderate to high yields. The hydrazinocarbonylation of iodobenzene using the above 1,1-disubstituted hydrazines resulted in a rather complex reaction mixture due to two major types of side-reactions: i) the deamination of the 3-amino-3-azabicyclo[3.3.0]octane, and ii) the double carbon monoxide insertion. In this way, in addition to the expected benzoylhydrazide derivative, phenylglyoxylhydrazide (double CO insertion product) and benzamide (‘deamination’ product) were also formed. By the appropriate modification of the reaction conditions, good selectivities towards the target compounds were achieved even in these cases. The formation of the products/side-products were rationalized on the basis of a simplified catalytic cycle.

Full text of DOI:10.1016/j.tet.2016.12.063

Accepted Manuscript
Aminocarbonylation (hydrazinocarbonylation) of iodoalkenes and iodoarenes
Máté Gergely, László Kollár
PII:
S0040-4020(16)31360-6
10.1016/j.tet.2016.12.063
TET 28355
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 15 June 2016
Revised Date: 21 December 2016
Accepted Date: 23 December 2016
Please cite this article as: Gergely M, Kollár L, Aminocarbonylation (hydrazinocarbonylation) of
iodoalkenes and iodoarenes, Tetrahedron (2017), doi: 10.1016/j.tet.2016.12.063.
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ACCEPTED MANUSCRIPT
Aminocarbonylation (Hydrazinocarbonylation) of Iodoalkenes and Iodoarenes.
M. Gergely, L. Kollár*
Graphical abstract
H
N
I
O
1–40 bar CO, 50 oC
Pd(OAc)2 / PPh3
N
+
N
H2N

ACCEPTED MANUSCRIPT
Aminocarbonylation (Hydrazinocarbonylation) of Iodoalkenes and Iodoarenes.
M. Gergely, L. Kollár*
Graphical abstract
H
N
I
O
1–40 bar CO, 50 oC
Pd(OAc)2 / PPh3
N
+
N
H2N
1

ACCEPTED MANUSCRIPT
Aminocarbonylation (Hydrazinocarbonylation) of Iodoalkenes and
Iodoarenes.
Máté Gergelya and László Kollár a,b,*
a) Department of Inorganic Chemistry, University of Pécs and Szentágothai Research Centre, H-7624
Pécs, P.O. Box 266, Hungary; e-mail: kollar@ttk.pte.hu
b) MTA-PTE Research Group for Selective Chemical Syntheses, H-7624 Pécs, Ifjúság u. 6., Hungary
Abstract: Iodoalkenes such as 1-iodocyclohexene, 4-tert-butyl-1-iodocyclohexene, α-
iodostyrene and 17-iodoandrost-16-ene were aminocarbonylated in palladium-
catalysed reaction using 1,1-disubstituted (cyclic) hydrazines (3-amino-3-
azabicyclo[3.3.0]octane and (S)-1-amino-2-methoxymethylpyrrolidine (SAMP)/(R)-1-
amino-2-methoxymethyl-pyrrolidine (RAMP)) as N-nucleophiles. The corresponding
hydrazides were formed in moderate to high yields. The hydrazinocarbonylation of
iodobenzene using the above 1,1-disubstituted hydrazines resulted in a rather complex
reaction mixture due to two major types of side-reactions: i) the deamination of the 3-
amino-3-azabicyclo[3.3.0]octane, and ii) the double carbon monoxide insertion. In
this way, in addition to the expected benzoylhydrazide derivative,
phenylglyoxylhydrazide (double CO insertion product) and benzamide (‘deamination’
product) were also formed. By the appropriate modification of the reaction conditions,
good selectivities towards the target compounds were achieved even in these cases.
The formation of the products/side-products were rationalised on the basis of a
simplified catalytic cycle.
Key-words: carbonylation, palladium, hydrazide, hydrazine, carbon monoxide
2

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1. Introduction
The widely used palladium-catalysed amino- and alkoxycarbonylation reactions of aryl halides are
based on the seminal work of Heck et al. It was discovered that aryl halides, especially aryl bromides and
iodides undergo carbonylation reaction in the presence of primary/secondary amines and alcohols used as N-
and O-nucleophiles, respectively.1 The synthetic importance of these reactions have been illustrated by the
variation in structure of both the substrate and nucleophile.2-6 These carbonylations are among the most
important homogeneous catalytic reactions of synthetic importance and have found use in industrial
applications.7,8
Soon after the discovery of aminocarbonylation of haloaromatics, their synthetic analogues, i.e., iodo-
and bromoalkenes as well as the corresponding enol-triflate surrogates have also been synthesized and
transferred to the corresponding α,β-unsaturated carboxamides in palladium-catalysed aminocarbonylations.5,6
The synthesis of unsubstituted hydrazides is a straightforward methodology for aromatics, however
quite difficult for α,β-unsaturated hydrazides which usually undergo undesired Michael-type cyclization.9
Although the nucleophilic properties of alkyl- and aryl-hydrazine derivatives as well as the importance of their
hydrazides are well known,10 their synthesis via the corresponding ester needs special reaction conditions, for
instance, the application of organoaluminium reagents.11
Although transition metal catalysed reactions could provide efficient solutions for the synthesis of
carboxylic acid derivatives such as amides, esters, anhydrides, etc. from their building blocks, there are only a
very few examples for the application of substituted hydrazines as N-nucleophiles in palladium-catalysed
carbonylations. Steroidal hydrazides were prepared in hydrazinocarbonylation and used for further ring-closure
reactions.12-14 Diiodoaromatics were reacted with hydrazines under a carbon monoxide atmosphere leading to
tetrahydrophthalazine derivatives.15 Sulfonylhydrazides (aminosulfonamides) were synthesised in palladium-
catalysed reactions using (SO2)2•DABCO adduct as sulfur dioxide source and the corresponding 1,1-
disusbstituted hydrazines.16
As a part of our systematic investigations regarding structure–reactivity and structure–selectivity
relationships in palladium-catalysed carbonylation reactions, the above 1,1-disubstituted hydrazines of
practical interest17,18 were used. It is worth noting that the iodoalkene-based aminocarbonylation reaction,
described below provided a facile methodology even for the otherwise hardly available α,β-unsaturated
hydrazides.
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2. Results and discussion
2.1. Aminocarbonylation of iodoalkenes in the presence of 3-amino-3-azabicyclo[3.3.0]octane and SAMP /
RAMP as cyclic (1,1-substituted) hydrazines
1-Iodocyclohexene (1), 4-tert-butyl-1-iodocyclohexene (2), α-iodostyrene (3) and 17-iodoandrost-16-ene
(4) were aminocarbonylated in the presence of palladium catalysts formed in situ by the reaction of
palladium(II) acetate and triphenylphosphine.19-21 Two 1,1-disubstituted (cyclic) hydrazines, such as 3-amino-
3-azabicyclo[3.3.0]octane (a) and (S)-1-amino-2-methoxymethylpyrrolidine (SAMP, b) / (R)-1-amino-2-
methoxymethylpyrrolidine (RAMP, c) (Scheme 1) were used as N-nucleophiles in DMF.
H
O
N
N
a
N
H2N
1a–4a
I
CO
Pd(OAc)2 / PPh3
1–4
OMe
OMe
H
O
N
b, c
N
N
H2N
1b–4b, 1c–4c
Scheme 1. Hydrazinocarbonylation of iodoalkenes (1-4) in the presence of 3-amino-3-
azabicyclo[3.3.0]octane (a) and SAMP (b) or RAMP (c) as N-nucleophile
The aminocarbonylation of iodoalkenes (1-4) with a resulted in the high-yielding formation of the α,β-
unsaturated hydrazide products (1a-4a) in all cases (Table 1). The reaction is highly chemoselective, no further
products could be detected. The increase in carbon monoxide pressure had no influence on the selectivity, that
is, no double carbon monoxide insertion leading to 2-ketocarboxamides took place (entries 3 and 5).
Practically complete conversion was obtained in all cases in 4 h enabling facile isolation of the target products.
The high reactivity of iodoalkenes (1a-4a) towards nucleophile a can be illustrated by the
hydrazinocarbonylation of 1 providing conversion of 2%, 10%, 51% and 98% in 0.5 h, 1 h, 2 h and 4h,
respectively.
All products were isolated in high analytical purity (>98%) from reaction mixtures when the substrates
were practically fully converted (Table 1). Good to excellent yields were obtained and the target compounds
were fully characterised (See Experimental).
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Table 1. Palladium-catalysed hydrazinocarbonylation of iodoalkenes (1–4) in the presence of 3-amino-3-
azabicyclo[3.3.0]octane (a) a)
entry Substrate p(CO)
[bar]
Isolated yield [%]
(compound)
1
2
3
4
5
6
1
1
1
2
2
3
3
4
83 (1a)
69 (2a)
79 (2a)
54 (3a)
64 (3a)
53 (4a)
40
1
40
1
a) Reaction conditions (unless otherwise stated): 1 mmol of substrate (1–4); 1.2 mmol of a; 0.025 mmol of
Pd(OAc)2; 0.05 mmol of PPh3; 0.5 mL of triethylamine; 10 mL of DMF, 50 oC; 4 h.
Similarly, carboxamides 1b–4b or 1c–4c were obtained exclusively when the above iodoalkene
substrates, 1–4 were reacted with b (or c) under atmospheric carbon monoxide pressure (Table 2). As above,
the reaction was practically complete in 4 h resulting in good to excellent isolated yields. As for the substrates,
the only exception was 3. In spite of the full conversion and good chemoselectivity, the isolation in high yields
was unsuccessful.
When SAMP (or RAMP), i.e., the enantiomerically pure hydrazine derivative was used, a 1/1 mixture
of two diastereoisomers was formed in the hydrazinocarbonylation of the chiral substrate 2 applied always as a
racemic mixture. On the other hand, the diastereoselectivity of the hydrazinocarbonylation was investigated
using (R/S)-1-amino-2-methoxymethylpyrrolidine as racemate (b/c=1/1). No diastereoselection was observed,
that is, ca. a 1/1 mixture of the two diastereoisomers (4a/4b) were obtained in the presence of 2.2 equivalents
of racemic 1-amino-2-methoxymethylpyrrolidine and 4 as a substrate (Table 2).
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Table 2. Hydrazinocarbonylation of iodoalkenes (1–4) in the presence of (S)-1-amino-2-
methoxymethylpyrroplidine (SAMP, b) / (R)-1-amino-2-methoxymethylpyrrolidine (RAMP, c) a)
entry substrate nucleophile Isolated yield [%]
(compound)
1
2
1
1
2
2
3
3
4
4
4
c
b
88 (1c)
80 (1b)
98 (2c)
3
c
4
b
88 (2b)
40 (3c)
5
c
6
b
39 (3b)
99 (4c)
7
c
8
9 b)
b
84 (4b)
88 (4b/4c)c)
b/c
a) Reaction conditions: 1 mmol of substrate (1–4); 0.025 mmol of Pd(OAc)2; 0.05 mmol of PPh3; 1.2
mmol of N-nucleophile (b or c); 0.5 mL of triethylamine; 10 mL of DMF, 50 oC; p(CO)=1 bar, 4 h.
b) 2.2 mmol of racemic b/c was used.
c) The two epimers were obtained in a ratio of ca. 1/1.
2.2 Hydrazinocarbonylation of iodobenzene in the presence of 3-amino-3-azabicyclo[3.3.0]octane as cyclic
(1,1-disubstituted) hydrazine
As a comparison to iodoalkenes, the aminocarbonylation of iodobenzene (5) was carried out under similar
conditions (Scheme 2). The detailed analysis of the reaction mixtures revealed that 5 is much less reactive than
1–4 in palladium-catalysed hydrazinocarbonylation and in general, rather complex mixtures can be obtained.
In addition to the expected products, benzoic hydrazide (5a) and phenylglyoxylic hydrazide (6a) formed via
mono and double carbon monoxide insertion, respectively, further types of side-products were identified. First,
due to the relatively low reactivity of the substrate and the long reaction times, the N,N-dimethylbenzamide (7)
and N,N-dimethylphenylglyoxylamide (8) were formed. Second, deamination of nucleophile a yielded the
formation of two additional carboxamide and 2-ketocarboxamide-type products (9 and 10, respectively)
containing the 3-azabicyclo[3.3.0]octane moiety only.
6

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O
H
N
O
I
CO
N
N
+
N
Pd(OAc)2 / PPh3
+
N
O
H
R
H2N
DMF
R
R
5 (R = H)
a
5a
11a
17a
6a
12a
18a
11 (R = tBu)
17 (R = CF3)
N
N
O
N
O
O
N
O
O
O
R
R
R
R
7,13,19
8,14,20
9,15,21
10,16,22
Scheme 2. Hydrazinocarbonylation of iodobenzene (5), 4-tert-butyliodobenzene (11) and 4-
(trifluoromethyl)-iodobenzene (17) in the presence of 3-amino-3-azabicyclo[3.3.0]octane (a) as N-nucleophile
The formation of N,N-dimethylcarboxamide (7) and N,N-dimethylglyoxylamide (8) derivative in the presence
of DMF is known in carbonylations. That is, the solvent (DMF) served also as a source of amino or carbamoyl
moieties. A similar side-reaction has been observed recently using supported palladium catalysts in the
carbonylation of iodobenzene.22 Furthermore, the various roles of DMF as a reagent, among them as a source
of CO, NMe2, CONMe2 have also been reviewed.23
However, the loss of the amino group in hydrazinocarbonylations, to the best of our knowledge, is
unprecedented. In these cases a served as a precursor of a pyrrolidine type nucleophile whose application
might result in carboxamide compounds (9, 15, 21) and 2-ketocarboxamide compounds (10, 16, 22) in mono-
and double carbon monoxide insertion, respectively.
The use of Pd/PPh3 ‘in situ’ catalyst resulted in a complex reaction mixture (Table 3, entry 1). The benzoyl
hydrazide (5a) can be obtained as major product at higher temperature (entry 2). Similar yields of 5a and
higher reactivity was observed using xantphos as ligand (entry 4). The deamination of a and the acylation of
the N-nucleophile formed took place in high extent in toluene (Table 3, entry 3).
Two further iodobenzenes containing electron releasing (4-tert-butyliodobenzene, 11) and electron-
withdrawing groups (4-(trifluoromethyl)iodobenzene, 17) were also tested as a substrate (Table 3, entry 5 and
6). Using 17 as a substrate the carboxamide side-products (19, 21) were obtained in small amount and the
corresponding hydrazide 17a was isolated as a target compound. (Products 18a, 20 and 22, whose analogues
were obtained as minor products with substrate 5, were not formed even in traces.) However, 11 showed low
reactivity and the product composition was also rather different: carboxamides (13, 15) were obtained in large
7

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amount while the target hydrazide (11a) was formed in 29% only, regarding the converted substrate. (Products
12a and 16, whose analogues were obtained with substrate 5, were not formed even in traces.)
The carbonylation reactions carried out under 40 bar CO pressure resulted in the preferred formation of
phenylglyoxylhydrazide (6a) formed via double carbonylation (enries 7-9) while hydrazide 5a is also present
in the reaction mixtures. Higher amount of the target hydrazide (5a) and ketohydrazide (6a) were obtained at
higher temperatures (entry 8). Surprisingly, the decarbonylation of 6a to 5a was observed in elevated reaction
times (entry 9).
It is worth noting that the formation of a tetrahydropyridazine derivative (23) (Scheme 3) possessing the 3,4-
diazabicyclo[4.3,0]non-2-ene framework24 was also observed under 40 bar of CO (entry 6). The formation of
the diaza-nucleophile can be explained by the oxidation of a with the iodoamine formed in situ (See Scheme 4,
cycle-C).
O
H
+ NH2I
- NH4I
PhI, CO
[Pd]
N
N
N
N
H2N N
23
a
Scheme 3. Formation of the ring expansion product (tetrahydropyridazine derivative) used as nucleophile
The formation of the above products can be rationalized by simplified catalytic cycles (Scheme 4). The
oxidative addition of the iodoaromatic substrate (5) onto palladium(0) complex, the activation of carbon
monoxide and its insertion into the Pd-aryl bond resulted in the formation of the acyl complex (C). The
coordination of the hydrazine derivative and the consecutive loss of hydrogen iodide gave the palladium(II)-
amido-acyl complex (E) which undergoes reductive elimination leading to palladium(0) complex and 5a
(cycle-A).
The amido-acyl complex is apt to coordinate a ‘second’ carbon monoxide, which is inserted into the
palladium(II)-amide bond resulting in the acyl-carbamoyl-palladium(II) species (G). The reductive elimination
provided the double carbonylation product (6a) (cycle-B).
It can be supposed that the acyl-iodo complex (C) is able to coordinate the hydrazine (a) via more nucleophilic
(however, sterically more hindered) ‘ring-nitrogen’ donor yielding complex H. The loss of the amino group
takes place probably in this step forming amido-acyl-complex (I) which provides 9 via reductive elimination
(cycle-C). (A further cycle rationalizing the formation of 10 is omitted for clarity. As above, carbon monoxide
insertion into palladium(II)-N bond of complex I leads to the corresponding carbamoyl complex which might
be responsible for the formation of the phenylglyoxyloyl hydrazide 10.)
8

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Table 3. Palladium-catalysed hydrazinocarbonylation of iodobenzenes (5, 11, 17) in the presence of 3-amino-
3-azabicyclo[3.3.0]octane (a) a)
entry Substr. p(CO) Temp. Conv.
Ratio of the reaction productsb) [%]
[bar]
[oC]
[%]
5a
18
67
7
6a
3
7
8
0
9
10
4
1
2
3c)
4d)
5
1
1
1
1
1
50
70
70
50
70
45
76
16
16
0
59
12
93
11
5
5
0
5
0
>98
>98
49
0
0
0
5
65
0
11
13
0
5
29
0
41
7
23
0
11
(11a) (12a) (13)
83
(17a) (18a) (19)
(14)
(15)
(16)
6
1
70
92
0
9
0
(20)
8
(21)
0
(22)
17
7e)
8
9f)
40
40
40
50
70
70
88
14
48
75
31
45
17
9
3
0
9
0
0
10
4
10
0
5
5
5
>98
>98
8
0
a) Reaction conditions (unless otherwise stated): 1 mmol of substrate (5 or 11 or 17); 1.2 mol of a; 0.025
mmol of Pd(OAc)2; 0.05 mmol of PPh3; 0.5 mL of triethylamine; solvent: 10 mL of DMF; reaction time:
24 h. (The selective formation of a given product obtained by the modification of the reaction conditions is
indicated by underlined numbers.)
b) Determined by GC-MS. (In case of substrates 11 and 17 the corresponding products (11a–16 and 17a–22,
respectively) are indicated in the table.)
c) 10 mL of toluene as solvent.
d) Pd/xantphos catalyst
e) 17% of tetrahydropyridazine side product (23) was formed.
f) Reaction time: 48 h.
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N
N
CO
NH
O
NH
Pd(CO)Ln
PdLn
F
Ar
G
Ar
N
N
O
5a
9
O
NH
Ar
O
N
cycle-B
O
Ar
O
NH
6a
Ar
O
PdLn
N
NH PdLn
Ar
A5r-I
O E
Et3NHI
cycle-C
Et3N
NH2 PdILn
LnPdI
Ar
A
N
D
cycle-A
O
Ar
CO
C
B
I
LnPdI
Ar
LnPdI(CO)
N
PdLn
O
N
NH2
Ar
O
Ar
H
NH2
NH2I
N
PdILn
Ar
O
Scheme 4. Simplified catalytic cycles leading to products formed in hydrazinocarbonylation of
iodobenzene (5) in the presence of 3-amino-3-azabicyclo[3.3.0]octane
Conclusions
Iodoalkenes underwent palladium-catalysed hydrazinocarbonylation using 1,1-disubstituted (cyclic)
hydrazines (3-amino-3-azabicyclo[3.3.0]octane and (S)-1-amino-2-methoxymethylpyrrolidine (SAMP)/(R)-1-
amino-2-methoxymethyl-pyrrolidine (RAMP) as N-nucleophiles. The reaction proved to be completely
chemoselective and the unsaturated hydrazides were isolated in moderate to high yields. However, when
iodobenzene was used as substrate, the hydrazinocarbonylation was accompanied by side reactions such as
deamination of the nucleophile followed by aminocarbonylation with the pyperidine derivative, and
aminocarbonylation with DMF as amine source.
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3. Experimental
3.1. General procedures
13
1H and C NMR spectra were recorded in CDCl3 on a Bruker Avance III 500 spectrometer at 500 and
125.7 MHz, respectively. Chemical shifts δ are reported in ppm relative to CHCl3 (7.26 and 77.00 ppm for 1H
and 13C, respectively). Elemental analyses were measured on a 1108 Carlo Erba apparatus. Samples of the
catalytic reactions were analysed with a Hewlett Packard 5830A gas chromatograph fitted with a capillary
o
o
column coated with OV-1 (internal standard: naphthalene; injector temp. 250 C; oven: starting temp. 50 C
o
o
o
(hold-time 1 min), heating rate 15 C.min-1, final temp. 320 C (hold-time 11 min); detector temp. 280 C;
carrier gas: helium (rate: 1 mL.min-1)). Samples of the catalytic reactions were analysed with an MS (Agilent
LC/MSD Trap XCT Plus) (electrospray ionizer, eluent: methanol (0.2 v/v% acetic acid)). The FT-IR spectra
were taken in KBr pellets using an IMPACT 400 spectrometer (Nicolet) applying a DTGS detector in the
region of 400–4000 cm-1, the resolution was 4 cm-1. The amount of the samples was ca. 0.5 mg.
1-Iodocyclohexene25 (1), 4-tert-butylcyclohexene25 (2), 1´-iodostyrene26 (3) and 17-iodoandrost-16-ene27
(4) were synthesised by the modified Barton-procedure.28,29 Iodobenzene and the amine nucleophiles were
purchased from Sigma-Aldrich and were used without further purification.
The synthesis of compounds 7,30,31 8,32 13,30,31 1432 and 1930 have already been described. The analytical
data obtained in our laboratory correspond well with those published. For the minor products (10, 15, 21) MS
data are given only, since the isolation in analytically pure form was unsuccessful.
3.2. Hydrazinocarbonylation (aminocarbonylation) of iodobenzene (5) in the presence of 3-amino-3-
azabicyclo[3.3.0]octane (a) under high carbon monoxide pressure
In a typical experiment Pd(OAc)2 (5.6 mg, 0.025 mmol), triphenylphosphine (13.2 mg, 0.05 mmol),
iodoalkene (1–4) (1 mmol), 1,1-disubstituted hydrazine (a, b or c) (1.2 mmol) and triethylamine (0.5 ml) were
dissolved in DMF (10 mL) under argon in a 100 mL autoclave. The autoclave was pressurized to the given
pressure by carbon monoxide. (Caution: High pressure carbon monoxide should only be used with adequate
ventillation (hood) using CO sensors as well.) The reaction was conducted for the given reaction time upon
o
stirring at 50 C and analyzed by GC and GC-MS. The mixture was then concentrated and evaporated to
dryness. The residue was dissolved in chloroform (20 ml) and washed with water (3x20 mL). The organic
phase was dried over Na2SO4, filtered and evaporated to a crystalline material or to a waxy residue. All
compounds were subjected to column chromatography (Silicagel 60 (Merck), 0.063–0.200 mm),
MeOH/EtOAc/CHCl3 (the exact ratios are specified in Characterization (3.4.) for each compound).
3.3. Hydrazinocarbonylation (aminocarbonylation) of iodoalkenes (1–4) in the presence of 3-amino-3-
azabicyclo[3.3.0]octane (a) under atmospheric carbon monoxide pressure
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In a typical experiment Pd(OAc)2, triphenylphosphine, iodoalkene, hydrazine nucleophile and
triethylamine were dissolved in DMF (for the quantity of the reagents See Section 3.2) under argon in a 100
mL three-necked flask equipped with a gas inlet, reflux condenser with a balloon (filled with argon) at the top.
The atmosphere was changed to carbon monoxide. The reaction was conducted for 4 h upon stirring at 50 oC
and analysed by GC and GC-MS. The mixture was then concentrated and evaporated to dryness and worked-
up as described in Section 3.2.
3.4. Characterization of the products
N-(3-azabicyclo[3.3.0]octane-3-yl)cyclohex-1-enecarboxamide (1a). Yield: 193.9 mg (83%), pale
yellow needles, sublimation point 116–117 °C; [Found: C, 71.55; H, 9.51; N, 11.69; C14H22N2O requires C,
71.76; H, 9.46; N, 11.95%]; Rf (3% MeOH, 97% CHCl3) 0.62; δH (500 MHz, CDCl3) 6.54 (1H, br s, =CH),
6.25 (1H, br s, NH), 3.29 (2H, br s, NCHeqHax), 2.67 (2H, br s, CH(Cp)), 2.36 (2H, br s, NCHaxHeq), 2.24 (2H,
br s, CH2), 2.13–2.17 (2H, m, CH2), 1.56–1.70 (8H, m, 4xCH2), 1.49 (2H, br s, CH2); δC (125.7 MHz, CDCl3)
167.0, 133.1, 132.8, 62.6, 40.5, 32.2, 25.5, 25.3, 24.4, 22.1, 21.6. IR (KBr ν (cm-1)) 3223 (NH), 1657 (CON);
MS m/z (rel int.): 234 (8, M+), 190 (6), 125 (17), 110 (100), 81 (26), 79 (29).
4-(tert-butyl)-N-(3-azabicyclo[3.3.0]octane-3-yl)cyclohex-1-enecarboxamide (2a). Yield: 229.1 mg
(79%), yellow solid, sublimation point 121–122 °C; [Found: C, 74.35; H, 10.21; N, 9.49; C18H30N2O requires
C, 74.44; H, 10.41; N, 9.64%]; Rf (10% EtOAc, 90% CHCl3) 0.34; δH (500 MHz, CDCl3) 6.56 (1H, br s,
=CH), 6.29 (1H, br s, NH), 3.29 (2H, br s, NCHeqHax), 2.67 (2H, br s, CH), 2.34–2.46 (3H, m, NCHaxHeq and
3-CHeqHax), 2.12–2.23 (2H, m, 3-CHaxHeq and 6-CHeqHax), 1.86–1.94 (2H, m, 5-CHeqHax and 6-CHaxHeq),
1.45–1.96 (6H, m, CH2), 1.27 (1H, m, 4-CH), 1.16 (1H, qd, 12.2, 4.9 Hz, 5-CHaxHeq); δC (125.7 MHz, CDCl3)
166.8, 133.7, 132.6, 62.6, 43.4, 40.5, 32.2, 32.1, 27.1, 27.0, 25.9, 25.5, 23.6. IR (KBr ν (cm-1)) 3220 (N-H),
1658 (CON); MS m/z (rel int.): 290 (<1; M+), 275 (2), 246 (6), 165 (3), 125 (23), 110 (100), 81 (27), 57 (17).
N-(3-azabicyclo[3.3.0]octane-3-yl)atropic carboxamide (3a). Yield: 163.8 mg (64%), orange solid, mp
94–95 °C; [Found: C, 74.74; H, 7.71; N, 10.69; C16H20N2O requires C, 74.97; H, 7.86; N, 10.93%]; Rf (20%
EtOAc, 80% CHCl3) 0.45; δH (500 MHz, CDCl3) 7.40 (br s, 5H, CH(Ph)), 6.27 (1H, s, NHCO), 6.09 (1H, d,
0.9 Hz, =CH), 5.65 (1H, d, 0.9 Hz, =CH), 3.28 (2H, t, 8.2 Hz, NCHeqHax), 2.68 (2H, br s, CH), 2.36 (2H, dd,
8.2, 6.1 Hz, NCHaxHeq), 1.45-1.67 (6H, m, CH2); δC (125.7 MHz, CDCl3) 165.6, 143.9, 136.7, 128.7, 128.6,
127.9, 121.9, 62.4, 40.5, 32.2, 25.5. IR (KBr ν (cm-1)) 3233 (N-H), 1654 (CON); MS m/z (rel int.): 256 (2),
240 (7), 211 (16), 183 (6), 146 (23), 125 (47), 110 (63), 103 (100), 81 (47), 77 (43), 67 (10), 53 (11), 51 (9).
12

ACCEPTED MANUSCRIPT
N-(3-azabicyclo[3.3.0]octane-3-yl)androst-16-en-17-carboxamide (4a). Yield: 218.6 mg (53%), white
crystal, mp 93–94 °C; [Found: C, 78.79; H, 10.15; N, 6.59; C27H42N2O requires C, 78.97; H, 10.31; N,
6.82%]; Rf (2% MeOH, 98% CHCl3) 0.55; δH (500 MHz, CDCl3) 6.28 (1H, br s, =CH), 6.20 (1H, s, NHCO),
3.22 (2H, br s, NCHeqHax), 2.65 (2H, br s, CH), 2.44 (2H, br s, NCHaxHeq), 2.19 (1H, ddd, 16.2, 5.8, 2.8 Hz,
15- CHeqHax), 0.75-2.00 (27H, m, androstane skeleton protons and 3xCH2), 0.99 (3H, s, 18-CH3), 0.83 (3H, s,
19-CH3); δC (125.7 MHz, CDCl3) 164.4, 149.8, 135.4, 62.5, 56.8, 55.2, 47.3, 46.8, 40.5, 38.5, 36.5, 35.0, 33.9,
32.4, 32.0, 31.7, 29.1, 28.9, 26.8, 25.7, 22.2, 20.7, 16.6, 12.2. IR (KBr ν (cm-1)) 3279 (N-H), 1646 (CON). MS
m/z: 411 (MH+), 433 (MNa+), 449 (MK+); MS2 (tandem MS) of MH+ (m/z (rel. int.): 257 (67), 153 (100).
(R)-N-(2-(methoxymethyl)pyrrolidin-1-yl)cyclohex-1-ene carboxamide (1c). Yield: 210.2 mg (88%);
pale yellow needle crystal, mp 92–93 °C; [Found: C, 65.33; H, 9.55; N, 11.52; C13H22N2O2 requires C, 65.52;
H, 9.30; N, 11.75%]; Rf (3% MeOH, 97% CHCl3) 0.53; δH (500 MHz, CDCl3) 6.77 (1H, br s, NH), 6.57 (1H,
br s, =CH), 3.48 (1H, dd, 9.5, 5.2 Hz, OCHaHb), 3.43 (1H, dd, 9.5, 5.2 Hz, OCHaHb), 3.35 (3H, s, OCH3), 3.32
(1H, dt, 8.5, 5.5 Hz, NCHeqHax), 3.15 (1H, tt, 7.8, 5.2 Hz, NCH), 2.91 (1H, q, 8.5 Hz, NCHaxHeq), 2.24 (2H, br
s, CH2), 2.14–2.18 (2H, m, CH2), 2.04 (1H, dq, 12.7, 7.8 Hz, 3-CHeqHax), 1.84–1.90 (2H, m, 4-CH2), 1.59–
1.71 (5H, m, 2xCH2 and 3-CHaxHeq); δC (125.7 MHz, CDCl3) 167.6, 133.2, 132.9, 75.3, 64.0, 59.2, 55.2, 26.6,
25.3, 24.3, 22.1, 21.5, 21.4. IR (KBr ν (cm-1)) 3217 (NH), 1658 (CON); MS m/z (rel int.): 238 (1>, M+), 206
(5), 193 (100), 129 (5), 114 (47), 109 (23), 97 (29), 85 (15), 81 (19).
4-(tert-butyl)-N-((R)-2-(methoxymethyl)pyrrolidin-1-yl)cyclohex-1-ene carboxamide (2c) (isolated as a
ca. 50/50 mixture of two rotamers). Yield: 288.7 mg (98%), yellow viscous oil; [Found: C, 69.47; H, 10.43; N,
9.30; C17H30N2O2 requires C, 69.35; H, 10.27; N, 9.51%]; Rf (3% MeOH, 97% CHCl3) 0.52; δH (500 MHz,
CDCl3) 6.78 (1H, br s, NH), 6.59 (1H, dd, 5.2, 2.4 Hz, =CH), 3.48 (1H, dd, 9.5, 5.3 Hz, OCHaHb), 3.43 (1H,
dd, 9.5, 5.3 Hz, OCHaHb), 3.36 (3H, s, OCH3), 3.32 (1H, dq, 8.2, 5.8 Hz, NCHeqHax), 3.16 (1H, tt, 7.6, 5.3 Hz,
NCH), 2.92 (1H, qi, 8.2 Hz, NCHaxHeq), 2.43 (1H, m, CHeqHax), 2.13–2.25 (2H, m, CH2), 2.04 (1H, dq, 12.8,
7.6 Hz, CHeqHax), 1.82–1.95 (4H, m, 2xCH2), 1.66 (1H, dq, 12.8, 7.6 Hz, CHaxHeq), 1.28 (1H, tdd, 11.8, 4.6,
1.8 Hz, CH), 1.17 (1H, qd, 12.2, 4.9 Hz, CHaxHeq), 0.90 (9H, s, CH3); δC (125.7 MHz, CDCl3) 167.4,
133.8/133.7 (rotamers), 132.6/132.5 (rotamers), 75.3, 64.0/63.9 (rotamers), 59.2, 55.2/55.1 (rotamers), 43.4,
32.1, 27.1, 27.0, 26.6/26.5 (rotamers), 25.8, 23.6, 21.5. IR (KBr ν (cm-1)) 3236 (N-H), 1663 (CON); MS m/z
(rel int.): 294 (1>, M+), 279 (4), 263 (4), 249 (100), 182 (7), 165 (5), 129 (13), 114 (56), 57 (12).
(R)-N-(2-(methoxymethyl)pyrrolidin-1-yl)atropic carboxamide (3c). Yield: 57.2 mg (22%), yellow
viscous oil; [Found: C, 69.33; H, 7.80; N, 10.58; C15H20N2O2 requires C, 69.20; H, 7.74; N, 10.76%]; Rf (5%
13

ACCEPTED MANUSCRIPT
MeOH, 95% CHCl3) 0.65; δH (500 MHz, CDCl3) 7.44–7.36 (5H, m, Ph), 6.84 (1H, s, NHCO), 6.09 (1H, d, 1.2
Hz, =CH), 5.64 (1H, d, 1.2 Hz, =CH), 3.49 (1H, dd, 9.6, 5.6 Hz, OCHaHb), 3.43 (1H, dd, 9.6, 4.6 Hz,
OCHaHb), 3.32 (1H, m, NCHeqHax), 3.31 (3H, s, OCH3), 3.16 (1H, m, NCH), 2.91 (1H, q, 8.4 Hz, NCHaxHeq),
2.01 (1H, m, CHeqHax), 1.87 (2H, m, CH2), 1.65 (1H, m, CHaxHeq); δC (125.7 MHz, CDCl3) 166.1, 144.0,
136.7, 128.6, 128.5, 127.9, 121.7, 75.3, 63.8, 59.1, 55.1, 26.4, 21.4. IR (KBr ν (cm-1)) 3236 (N-H), 1670
(CON); MS m/z (rel int.): 260 (1, M+), 215 (100), 187 (13), 158 (3), 129 (10), 120 (5), 114 (6), 103 (48), 97
(13), 77 (25).
N-((R)-2-(methoxymethyl)pyrrolidin-1-yl)androst-16-en-17-carboxamide (4c). Yield: 408.7 mg (99%),
light yellow solid, mp 78–79 °C; [Found: C, 75.45; H, 10.34; N, 6.50; C26H42N2O2 requires C, 75.32; H,
10.21; N, 6.76%]; Rf (5% MeOH, 95% CHCl3) 0.69; δH (500 MHz, CDCl3) 6.74 (1H, br s, NH), 6.33 (1H, br
s, =CH), 3.48 (1H, dd, 9.6, 5.3 Hz, OCHaHb), 3.44 (1H, dd, 9.6, 5.3 Hz, OCHaHb), 3.36 (3H, s, OCH3), 3.32
(1H, dt, 8.4, 5.6 Hz, 24-CHeqHax), 3.20 (1H, tt, 7.6, 5.3 Hz, 21-CH), 2.96 (1H, q, 8.3 Hz, 24-CHaxHeq), 2.20
(1H, ddd, 16.3, 6.6, 3.1 Hz, 15-CHeqHax), 0.76–2.14 (25H, m, androstane skeleton protons and 2xCH2), 1.00
(3H, s, 18-CH3), 0.84 (3H, s, 19-CH3); δC (125.7 MHz, CDCl3) 165.0, 149.8, 135.7, 75.4, 63.6, 59.2, 56.9,
55.2, 55.1, 47.3, 46.7, 38.5, 36.5, 35.0, 33.9, 32.0, 31.6, 29.0, 28.9, 26.8, 26.6, 22.1, 21.5, 20.7, 16.5, 12.2. IR
(KBr ν (cm-1)) 3257 (NH), 1654 (CON); MS m/z (rel int.): 414 (1, M+), 399 (3), 383 (2), 369 (100), 302 (4),
285 (3), 257 (2), 207 (8), 129 (8), 114 (35).
N-((S)-2-(methoxymethyl)pyrrolidin-1-yl)androst-16-en-17-carboxamide (4b). Yield: 348.5 mg (84%),
yellow solid, mp 118–119 °C; [Found: C, 75.54; H, 10.38; N, 6.52; C26H42N2O2 requires C, 75.32; H, 10.21;
N, 6.76%];Rf (5% MeOH, 95% CHCl3) 0.69; δH (500 MHz, CDCl3) 6.75 (1H, br s, NH), 6.32 (1H, br s, =CH),
3.48 (1H, dd, 9.5, 5.5 Hz, OCHaHb), 3.42 (1H, dd, 9.5, 5.5 Hz, OCHaHb), 3.36 (3H, s, OCH3), 3.30 (1H, dt,
8.5, 5.5 Hz, 24-CHeqHax), 3.22 (1H, tt, 7.6, 5.5 Hz, 21-CH), 2.97 (1H, q, 8.5 Hz, 24-CHaxHeq), 2.20 (1H, ddd,
16.3, 6.4, 3.2 Hz, 15-CHeqHax), 0.75–2.13 (25H, m, androstane skeleton protons and 2xCH2), 1.00 (3H, s, 18-
CH3), 0.83 (3H, s, 19-CH3); δC (125.7 MHz, CDCl3) 165.1, 149.8, 135.7, 75.3, 63.6, 59.1, 56.8, 55.2, 55.0,
47.3, 46.8, 38.5, 36.5, 35.0, 33.8, 32.0, 31.6, 29.0, 28.9, 26.8, 26.6, 22.1, 21.6, 20.7, 16.6, 12.2. IR (KBr ν (cm-
1)) 3245 (N-H), 1649 (br s, CON); MS m/z (rel int.): 414 (1, M+), 399 (4), 369 (100), 281 (6), 207 (7), 129 (7),
114 (47).
N-(3-azabicyclo[3.3.0]octane-3-yl)benzamide (5a). Yield: 65.6 mg (28%), colorless needles, sublimation
point 118–119 °C; [Found: C, 73.18; H, 7.97; N, 12.01; C14H18N2O requires C, 73.01; H, 7.88; N, 12.16%]; Rf
(10% EtOAc, 90% CHCl3) 0.28; δH (500 MHz, CDCl3) 7.75 (2H, d, 7.6 Hz, Hortho(Ph)), 7.51 (1H, t, 7.3 Hz,
14

ACCEPTED MANUSCRIPT
Hpara(Ph)), 7.43 (2H, t, 7.6 Hz, Hmeta(Ph)), 6.72 (1H, br s, NH), 3.38 (2H, t, 7.8 Hz, NCHeqHax), 2.73 (2H, br s,
CH), 2.49 (2H, dd, 7.8, 6.1 Hz, NCHaxHeq), 1.50–1.74 (6H, m, CH2); δC (125.7 MHz, CDCl3) 166.0, 133.9,
131.5, 128.6, 127.0, 62.7, 40.5, 32.2, 25.6. IR (KBr ν (cm-1)) 3212 (NH), 1643 (CON); MS m/z (rel int.): 230
(<1, M+), 125 (40), 110 (100), 105 (42), 81 (50), 77 (58), 51 (20).
N-(3-azabicyclo[3.3.0]octane-3-yl)phenylglyoxylamide (6a). Yield: 32.7 mg (13%), white crystal,
sublimation point 125–126 °C; Rf 0.53 (20% EtOAc, 80% CHCl3); (ca. 1/2 mixture of two C(O)N rotamers)
δH (500 MHz, CDCl3) 8.33/7.95 (minor/major) (2H, d, 7.3 Hz, Hortho(Ph)), 7.64 (1H, t, 7.3 Hz, Hpara(Ph)),
7.53/7.49 (major/minor) (2H, t, 7.9/7.6 Hz, Hmeta(Ph)), 7.34 (1H, br s, NH), 3.28/2.73 (minor/major) (2H, t, 8.1
Hz, NCHeqHax), 2.73/2.35 (minor/major) (2H, br s, CH), 2.58/2.53 (major/minor) (2H, d/dd, 8.2/8.5, 5.5 Hz,
NCHaxHeq), 1.50–1.74 (minor) (6H, m, CH2), 1.50–1.61 (major) (2H, m, CH2), 1.19–1.35 (major) (2H, m,
CH2), 0.90 (major) (2H, br s, CH2); δC (125.7 MHz, CDCl3) 191.5/188.2 (major/minor), 169.5/159.7
(major/minor), 134.5/133.9 (minor/major), 133.3, 131.1/128.7 (minor/major), 128.6/128.5 (major/minor),
62.5/62.4 (major/minor), 40.5/40.2 (minor/major), 33.5/32.3 (major/minor), 26.2/25.7 (major/minor). IR (KBr
ν (cm-1)) 3248 (NH), 1695 (CO), 1686 (CO), 1677 (CON), 1656 (CON); MS m/z (rel int.): 258 (<2, M+), 185
(11), 125 (100), 110 (89), 105 (83), 81 (76), 77 (95), 67 (17), 51 (35).
N-(3-azabicyclo[3.3.0]octane-3-yl)-4-(tert-butyl)benzamide (11a). Yield: 56.1 mg (20%), yellow viscous
oil; [Found: C, 75.55; H, 9.02; N, 9.60; C18H26N2O requires C, 75.48; H, 9.15; N, 9.78%]; Rf (10% EtOAc,
90% CHCl3) 0.39; δH (500 MHz, CDCl3) 7.69 (2H, d, 8.2 Hz, Hortho(Ph)), 7.44 (2H, d, 8.2 Hz, Hmeta(Ph)), 6.80
(1H, br s, NH), 3.35 (2H, t, 7.6 Hz, NCHeqHax), 2.71 (2H, br s, CH), 2.49 (2H, t, 7.6 Hz, NCHaxHeq), 1.48–1.74
(6H, m, CH2), 1.34 (9H, s, CH3); δC (125.7 MHz, CDCl3) 165.9, 155.0, 131.0, 126.8, 125.5, 62.6, 40.5, 34.9,
32.2, 31.2, 25.6. IR (KBr ν (cm-1)) 3249 (NH), 1651 (CON); MS m/z (rel int.): 286 (<1, M+), 242 (7), 162
(30), 161 (30), 125 (22), 110 (100), 81 (22).
N-(3-azabicyclo[3.3.0]octane-3-yl)-4-(trifluoromethyl)benzamide (17a). Yield: 175.4 mg (59%),
colorless needles, sublimation point 121–122 °C; [Found: C, 60.25; H, 5.90; N, 9.22; C15H17N2O2F3 requires
C, 60.40; H, 5.74; N, 9.39%]; Rf (2% MeOH, 98% CHCl3) 0.50; δH (500 MHz, CDCl3) 7.86 (2H, d, 7.9 Hz,
Hortho(Ph)), 7.70 (2H, d, 7.9 Hz, Hmeta(Ph)), 6.70 (1H, br s, NH), 3.37 (2H, t, 7.6 Hz, NCHeqHax), 2.74 (2H, br
s, CH), 2.52 (2H, br s, NCHaxHeq), 1.50–1.74 (6H, m, CH2); δC (125.7 MHz, CDCl3) 164.8, 137.3, 133.1 (q,
32.7Hz, 4-C(Ph)), 127.6, 125.5, 123.7 (q, 272.5Hz, CF3), 62.4, 40.5, 32.2, 25.5. δF (470.4 MHz, CDCl3) -63.0
(s, CF3). IR (KBr ν (cm-1)) 3209 (NH), 1650 (CON), 1330 (νas, CF3), 1127 (νs, CF3); MS m/z (rel int.): 298 (2,
M+), 279 (2), 190 (5), 173 (35), 145 (54), 125 (100), 110 (96), 81 (88), 69 (23).
15

ACCEPTED MANUSCRIPT
3-benzoyl-3-azabicyclo[3.3.0]octane (9). Yield: 49.3 mg (23%), yellow viscous oil; Rf (20% EtOAc,
80% CHCl3) 0.38; δH (500 MHz, CDCl3) 7.38–7.49 (5H, m, Ph, 3.87 (1H, t, 8.9 Hz, NCHeqHax), 3.62 (1H, t,
8.9 Hz, NCHeqHax), 3.52 (1H, d, 8.5 Hz, NCHaxHeq), 3.21 (1H, d, 8.5 Hz, NCHaxHeq), 2.72 (1H, br s, CH), 2.65
(1H, br s, CH), 1.36–1.90 (6H, m, CH2); δC (125.7 MHz, CDCl3) 169.5, 137.3, 129.6, 128.2, 127.1, 55.3, 51.8,
43.8, 42.0, 32.3, 31.7, 25.6. MS m/z (rel int.): 215 (51, M+), 186 (15), 110 (5), 105 (100), 77 (62), 67 (12), 51
(13).
3-phenylglyoxyloyl-3-azabicyclo[3.3.0]octane (10). MS m/z (rel int.): 243 (<2, M+), 138 (93), 110 (30),
105 (77), 95 (82), 77 (100), 67 (32), 51 (29).
3-(4’-tert-butylbenzoyl)-3-azabicyclo[3.3.0]octane (15). MS m/z (rel int.): 217 (60, M+),.242 (11), 161
(100), 146 (18), 118 (21), 91 (11).
3-(4’-trifluoromethylbenzoyl)-3-azabicyclo[3.3.0]octane (21). MS m/z (rel int.): 283 (52, M+), 264 (8),
254 (16), 173 (100), 145 (55), 126 (7), 110 (6), 95 (8).
4-benzoyl-3,4-diazabicyclo[4.3.0]non-2-ene (23). MS m/z (rel int.): 228 (11, M+), 123 (11), 105 (100),
77 (63), 51 (14).
Acknowledgement: The authors thank the Hungarian Research Fund (K113177) and Developing
Competitiveness of Universities in the Transdanubian Region (SROP-4.2.1.B-10/2/KONV-2010-0002 and
SROP-4.2.2.A-11/1/KONV-2012-0065) for the financial support. The present scientific contribution is
dedicated to the 650th anniversary of the foundation of the University of Pécs, Hungary.
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