Home Convenient synthesis of the functionalized 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-enes via a three-component reaction
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Convenient synthesis of the functionalized 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-enes via a three-component reaction

  • Chang-Zhou Liu , Ying Han EMAIL logo , Wen-Jie Qi and Chao-Guo Yan EMAIL logo
Published/Copyright: September 24, 2016
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Heterocyclic Communications
From the journal Heterocyclic Communications Volume 22 Issue 5

Abstract

The three-component reaction of triphenylphosphine, dialkyl hex-2-en-4-ynedioate and arylidene-1,3-indanedione in dry DME at room temperature furnishes functionalized triphenylphosphanylidene-substituted 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-enes in 75–92% yields. 1H NMR spectra and X-ray diffraction analysis indicate that the trans-isomer is predominately formed and the reaction has very high diastereoselectivity.

Keywords: diastereoselectivity; electron-deficient alkyne; 1,3- indanedione; phosphine; spiro[cyclopentane-1,2′-indene]

Introduction

The nucleophilic phosphine-catalyzed annulations have emerged as one of powerful tools for the construction of diverse carbocyclic and heterocyclic systems [1], [2], [3], [4], [5]. The strategy of phosphine-catalyzed annulations includes addition of tertiary phosphine to electron-deficient allenes, alkynes, and modified allylic carbonates to generate active dipolar intermediates and subsequent cyclization with prevailing electrophiles to assembly of versatile five-membered carbo- and heterocycles [6], [7], [8], [9], [10], [11]. In these annulations, dialkyl acetylenedicarboxylates, alkyl propionates and aroylacetylenes are the most common used electron-deficient alkynes [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24]. In recent years, a new kind of electron-deficient alkyne, dialkyl hex-2-en-4-ynedioate, emerged as new versatile reactive substrate in the reaction [25], [26]. Dialkyl hex-2-en-4-ynedioate is easily obtained in a nearly quantitative yield by base-catalyzed dimerization of alkyl propiolate under mild conditions [27], [28]. Chuang and coworkers have established several phosphine-catalyzed cycloadditions of dimethyl hex-2-en-4-ynedioate with electrophiles containing C=O, C=C and C=N double bonds [29], [30], [31], [32], [33], [34], [35], [36]. We have also successfully developed a mutlicomponent reaction composed of triphenylphosphine and dialkyl hex-2-en-4-ynedioate for the efficient construction of diverse polycyclic and spiroheterocyclic systems [37], [38], [39], [40]. In these reactions, the initially formed active delocalized zwitter ion displays interesting multiple reactivity. In order to further demonstrate the potential synthetic values of the nucleophilic phosphine-catalyzed cyclization, herein we wish to report the three-component reaction of triphenylphosphine and dialkyl hex-2-en-4-ynedioate and 2-arylidene-1,3-indanediones for diastereoselective synthesis of the functionalized 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-enes.

Results and discussion

According to the previously established reaction conditions for the phosphine catalyzed reaction of dialkyl hex-2-en-4-ynedioate and phenacylideneoxindolines [38], [39], a mixture of equivalent amounts of triphenylphosphine (0.5 mmol), dimethyl hex-2-en-4-ynedioate (0.5 mmol) and 2-(4-methylbenzylidene)-1,3-indanedione (0.5 mmol) was stirred in dry dimethoxymethane at room temperature for several hours. After workup, the desired cycloaddition product 1d was isolated in about 60% yield. However, TCL analysis indicated the presence of 2-(4-methylbenzylidene)-1,3-indanedione in the solution. After using a slight excess of triphenylphosphine (0.60 mmol) and dimethyl hex-2-en-4-ynedioate (0.55 mmol), the yield of compound 1d increased to 76%. When the reaction was carried out in ice bath, the compound 1d was obtained in 88% yield. It should be pointed out that the reaction proceeds smoothly to give the pure product after washing with ethanol and there is no need for column chromatography. With these convenient conditions, various 2-arylidene-1,3-indanediones were employed for the reaction. The results are summarized in Scheme 1. As can be seen, the corresponding methyl esters 1a–j were obtained in 78–92% yields. The electronic and the steric effects of the substituent on the aryl group show little effect on the yields of products. The reactions of diethyl hex-2-en-4-ynedioate also afford the spiro compounds 1k,l in satisfactory yields of 75–80%.

Scheme 1
Scheme 1

All prepared spiro compounds were fully characterized by IR, HRMS, 1H, 13C and 31P NMR. Because there are two chiral carbon atoms in the newly-formed cyclopentene ring, two diastereoisomers (cis/trans isomers) might be formed. However, the NMR spectra always display a single set of absorptions for the characteristic groups in the molecule, which indicates that only one diastereoisomer is formed. For example, the 1H NMR spectrum of compound 1d shows a singlet at 5.04 ppm, a broad peak at 4.08 ppm and a singlet at 3.95 ppm for the three protons in the newly-formed cyclopentene ring. Other three singlets at 3.33, 3.04 and 2.30 ppm are the characteristic absorptions of the two methoxy groups and one methyl groups, respectively. The 31P spectrum displays a sharp singlet at 18.65 ppm for to the phosphanylidene group. The single crystal structures of the spiro compounds 1h, 1i and 1j were successfully determined by X-ray diffraction method (Figures 1–3). The three single crystals have similar structural and stereochemical pattern, in which the 5′-aryl group and 4′-carboxylate groups exist in trans-configuration. The C2=C3 double bond forms a conjugated system with a C=P double bond. In the molecule 1h, the lengths of the four C-P bonds are 1.740(3), 1. 817(3), 1.822(3) and 1.812(3), respectively. The first short bond is a C=P double bond. On the basis of NMR spectra and single crystal structures, it can be concluded that the obtained products 1a–l have trans-configuration and the three-component reaction has high diastereoselectivity.

Figure 1 The molecular structure of the spiro compound 1h.
Figure 1

The molecular structure of the spiro compound 1h.

Figure 2 The molecular structure of the spiro compound 1i.
Figure 2

The molecular structure of the spiro compound 1i.

Figure 3 The molecular structure of the spiro compound 1j.
Figure 3

The molecular structure of the spiro compound 1j.

To explain the formation of 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-enes 1, a plausible reaction mechanism is proposed in Scheme 2 which is based on the present experiments and previuosly reported similar observations [37], [38], [39], [40]. Initially, the addition of triphenylphosphine to dialkyl hex-2-en-4-ynedioate affords the expected reactive dipolar intermediate (A). Then, the addition of dipolar intermediate (A) to arylidene-1,3-indanedione results in formation of the adduct intermediate (B) with the resonance structure (C). Finally, the intramolecular coupling of positive charge with negative charge in intermediate (C) affords the polysubstituted 1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene 1. Because all three sequential reactions are retro-equilibrium reactions, the stable trans-isomer is predominatedly formed as main product in the final cylization step. In order to study the scope and limitations of this reaction, the structurally similar 2-arylidenedimedones and 2-arylidene barbituric acid were also employed as possible substrates. However, these attempted reactions did not give satisfactory yields of the expected products, which suggests that the reactivity of the dienophile plays an important role.

Scheme 2
Scheme 2

Conclusion

We have successfully developed an efficient synthetic protocol for the construction of 1′,3′-dihydro spiro[cyclopentane-1,2′-inden]-2-enes using a three-component reaction of triphenylphosphine, dialkyl hex-2-en-4-ynedioate and 2-arylidene-1,3-indanedione. The advantages of the reaction include readily available reagents, mild conditions, simple manipulation, satisfactory yields and high diastereoselectivity.

Experimental

General procedure for synthesis of products 1

A mixture of 2-arylidene-1,3-indanedione (0.5 mmol) and dialkyl hex-2-en-4-ynedioate (0.55 mmol) in dry dimethoxyethane (10 mL) was stirred in an ice bath for 10 min. Then, triphenylphosphine (0.6 mmol) was added slowly. The mixture was stirred at room temperature for about 12 h, after which time the solvent was removed by rotary evaporation at reduced pressure. The residue was crystallized from ethanol to give analytically pure product 1.

Methyl 2-(2-methoxy-2-oxo-1-(triphenyl-λ5-phosphanylidene)ethyl)-1′,3′-dioxo-5-phenyl-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1a)

Yellow solid; yield 80%; mp 238–240°C; 1H NMR (400 MHz, DMSO-d6): δ 8.01 (d, J=7.6 Hz, 1H, ArH), 7.95 (t, J=7.6 Hz, 1H, ArH), 7.86 (t, J=7.2 Hz, 1H, ArH), 7.62–7.57 (m, 4H, ArH), 7.45 (m, 6H, ArH), 7.27–7.16 (m, 9H, ArH), 6.57 (brs, 2H, ArH), 5.09 (s, 1H, CH), 4.11 (brs, 1H, CH), 3.96 (s, 1H, CH), 3.34 (s, 3H, OCH3), 3.04 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 198.6, 198.4, 171.9, 171.9, 142.0, 141.4, 137.9, 134.8, 134.7, 133.7, 133.6, 131.4, 131.4, 129.9, 128.3, 128.2, 127.9, 127.6, 127.2, 126.7, 123.6, 122.9, 121.3, 121.3, 64.8, 63.4, 63.3, 52.2, 51.6; 31P NMR (242 MHz, CDCl3): δ 18.69; IR (KBr): ν 3065, 2947, 2833, 2686, 1977, 1822, 1745, 1637, 1483, 1330, 1183, 1096, 995, 862 cm−1. ESI-HR-MS. Calcd for C42H34O6P ([M+H]+): m/z 665.2088. Found: m/z 665.2101.

Methyl 2-(2-methoxy-2-oxo-1-(triphenyl-λ5-phosphanylidene)ethyl)-1′,3′-dioxo-5-(m-tolyl)-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1b)

Yellow solid; yield 83%; mp 226–228°C; 1H NMR (400 MHz, DMSO-d6): δ 8.01 (d, J=7.6 Hz, 1H, ArH), 7.95 (t, J=7.6 Hz, 1H, ArH), 7.87 (t, J=7.6 Hz, 1H, ArH), 7.64–7.57 (m, 4H, ArH), 7.45 (m, 6H, ArH), 7.25 (m, 6H, ArH), 7.06 (d, J=6.4 Hz, 2H, ArH), 6.46–6.33 (m, 2H, ArH), 4.98 (s, 1H, CH), 4.13 (d, J=0.8 Hz, 1H, CH), 3.95 (s, 1H, CH), 3.33 (s, 3H, OCH3), 3.05 (s, 3H, OCH3), 2.13 (s, 3H, CH3); 13C NMR (100 MHz, CDCl3): δ 198.6, 198.4, 171.9, 171.9, 142.1, 141.4, 137.9, 137.1, 134.7, 134.6, 133.7, 133.7, 133.6, 131.4, 131.4, 130.5, 128.3, 128.2, 127.9, 127.8, 127.6, 127.0, 126.7, 123.6, 122.9, 109.9, 64.8, 63.3, 63.3, 52.2, 51.5, 21.3; 31P NMR (242 MHz, CDCl3): δ 18.67; IR (KBr): ν 3058, 3010, 2830, 2687, 2110, 1979, 1783, 1632, 1431, 1333, 1227, 1183, 1056, 918 cm−1. ESI-HR-MS. Calcd for C43H36O6P ([M+H]+): m/z 679.2244. Found: m/z 679.2271.

Methyl 2-(2-methoxy-2-oxo-1-(triphenyl-λ5-phosphanylidene) ethyl)-5-(3-methoxyphenyl)- 1′,3′-dioxo-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1c)

Yellow solid; yield 85%; mp 214–216°C; 1H NMR (400 MHz, DMSO-d6): δ 8.00 (d, J=7.2 Hz, 1H, ArH), 7.95 (t, J=7.6 Hz, 1H, ArH), 7.87 (t, J=7.2 Hz, 1H, ArH), 7.64 (d, J=7.2 Hz, 1H, ArH), 7.58 (t, J=7.2 Hz, 3H, ArH), 7.45 (t, J=7.2 Hz, 6H, ArH), 7.25 (m, 6H, ArH), 7.09 (t, J=8.0 Hz, 1H, ArH), 6.81 (d, J=8.0 Hz, 1H, ArH), 6.14 (d, J=6.2 Hz, 2H, ArH), 5.17 (s, 1H, CH), 3.99 (s, 1H, CH), 3.85 (d, J=0.8 Hz, 1H, CH), 3.62 (s, 3H, OCH3), 3.34 (s, 3H, OCH3), 3.07 (s, 3H, OCH3); 13C NMR (100 MHz, DMSO-d6): δ 203.0, 202.5, 176.3, 176.3, 164.1, 146.5, 145.7, 144.2, 141.1, 141.0, 138.3, 138.2, 137.1, 137.0, 134.1, 133.8, 133.7, 132.2, 131.3, 128.9, 127.9, 126.9, 120.4, 117.7, 69.5, 67.7, 67.6, 60.0, 56.7, 56.5, 54.1; 31P NMR (242 MHz, DMSO-d6): δ 18.21; IR (KBr): ν 3066, 2948, 2832, 2684, 2379, 2197, 2095, 1904, 1785, 1595, 1330, 1098, 922, 875 cm−1. ESI-HR-MS. Calcd for C43H36O7P ([M+H]+): m/z 695.2193. Found: m/z 695.2209.

Methyl 2-(2-methoxy-2-oxo-1-(triphenyl-λ5-phosphanylidene)ethyl)-1′,3′-dioxo-5-(p-tolyl)-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1d)

Yellow solid; yield 88%; mp 236–238°C; 1H NMR (400 MHz, DMSO-d6): δ 8.01 (d, J=7.6 Hz, 1H, ArH), 7.94 (t, J=7.6 Hz, 1H, ArH), 7.86 (t, J=7.2 Hz, 1H, ArH), 7.63 (d, J=7.2 Hz, 1H, ArH), 7.58 (t, J=7.6 Hz, 3H, ArH), 7.45 (m, 6H, ArH), 7.24 (m, 6H, ArH), 6.99 (d, J=8.0 Hz, 2H, ArH), 6.46 (s, 2H, ArH), 5.04 (s, 1H, CH), 4.08 (brs, 1H, CH), 3.95 (t, J=1.6 Hz, 1H, CH), 3.33 (s, 3H, OCH3), 3.04 (s, 3H, OCH3), 2.30 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6): δ 198.4, 198.0, 171.6, 171.6, 141.7, 141.0, 136.8, 136.3, 136.2, 135.0, 133.7, 133.6, 132.3, 132.3, 129.8, 129.0, 128.9, 128.8, 127.5, 126.5, 124.1, 123.2, 64.7, 62.8, 51.9, 51.8, 49.2, 21.1; 31P NMR (242 MHz, DMSO-d6): δ 18.65; IR (KBr): ν 3058, 2946, 2687, 2389, 2110, 1979, 1783, 1632, 1508, 1333, 1183, 1100, 994, 785 cm−1. ESI-HR-MS. Calcd for C43H36O6P ([M+H]+): m/z 679.2244. Found: m/z 679.2273.

Methyl 5-(4-tert-butylphenyl)-2-(2-methoxy-2-oxo-1-(triphenyl- λ5-phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1e)

Yellow solid; yield 78%; mp 248–250°C; 1H NMR (400 MHz, DMSO-d6): δ 8.01 (d, J=7.6 Hz, 1H, ArH), 7.94 (t, J=7.2 Hz, 1H, ArH), 7.86 (t, J=7.2 Hz, 1H, ArH), 7.63–7.57 (m, 4H, ArH), 7.45 (m, 6H, ArH), 7.27–7.18 (m, 8H, ArH), 6.48–6.46 (m, 2H, ArH), 5.16 (s, 1H, CH), 4.00 (m, 2H, CH), 3.34 (s, 3H, OCH3), 3.05 (s, 3H, OCH3), 1.29 (s, 9H, C(CH3)3); 13C NMR (100 MHz, CDCl3): δ 198.6, 198.3, 172.1, 172.1, 149.8, 142.2, 141.4, 134.7, 134.6, 134.6, 133.8, 133.7, 133.5, 133.4, 131.5, 131.4, 129.5, 128.3, 128.2, 127.6, 126.7, 124.7, 123.6, 123.0, 65.2, 52.0, 51.6, 34.4, 31.5, 31.2; 31P NMR (242 MHz, CDCl3): δ 18.72; IR (KBr): ν 2957, 2832, 2560, 2109, 1747, 1636, 1429, 1336, 1184, 1056, 923, 876, 787 cm−1. ESI-HR-MS. Calcd for C46H42O6P ([M+H]+): m/z 721.2714. Found: m/z 721.2734.

Methyl 5-(2-chlorophenyl)-2-(2-methoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro[cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1f)

Yellow solid, yield 90%; mp 222–224°C; 1H NMR (400 MHz, DMSO-d6): δ 7.94 (m, 2H, ArH), 7.85 (t, J=6.8 Hz, 1H, ArH), 7.65 (d, J=7.6 Hz, 1H, ArH), 7.60 (t, J=7.2 Hz, 3H, ArH), 7.47 (m, 6H, ArH), 7.34 (m, 6H, ArH), 7.24–7.20 (m, 3H, ArH), 6.96–6.94 (m, 1H, ArH), 5.26 (s, 1H, CH), 4.81(s, 1H, CH), 3.93 (d, J=0.8 Hz, 1H, CH), 3.33 (s, 3H, OCH3), 3.09 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 198.9, 198.7, 171.8, 171.8, 142.2, 141.8, 138.3, 138.2, 135.5, 134.7, 134.6, 133.6, 133.5, 132.1, 131.4, 131.4, 128.9, 128.5, 128.3, 128.3, 127.5, 126.6, 126.5, 123.4, 123.4, 123.4, 123.3, 123.0, 122.7, 64.0, 58.4, 58.3, 53.1, 51.6, 49.6; 31P NMR (242 MHz, CDCl3): δ 17.71; IR (KBr): ν 3066, 2948, 2830, 2685, 2095, 1908, 1823, 1709, 1637, 1519, 1432, 1330, 1052, 994, 800 cm−1. ESI-HR-MS. Calcd for C42H33ClO6P ([M+H]+): m/z 699.1698. Found: m/z 699.171.

Methyl 5-(2-bromophenyl)-2-(2-methoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1g)

Yellow solid, 88%; mp 226–228°C; 1H NMR (400 MHz, DMSO-d6): δ 7.98–7.91 (m, 2H, ArH), 7.86 (t, J=7.2 Hz, 1H, ArH), 7.65 (d, J=7.6 Hz, 1H, ArH), 7.60 (t, J=7.2 Hz, 3H, ArH), 7.51–7.46 (m, 6H, ArH), 7.41–7.33 (m, 7H, ArH), 7.24 (t, J=7.2 Hz, 1H, ArH), 7.14 (t, J=7.6 Hz, 1H, ArH), 6.86 (m, 1H, ArH), 5.17 (s, 1H, CH), 4.99 (s, 1H, CH), 3.90 (d, J=0.8 Hz, 1H, CH), 3.32 (s, 3H, OCH3), 3.11 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 198.9, 198.8, 171.7, 171.7, 142.4, 142.0, 138.7, 138.6, 137.3, 134.8, 134.7, 133.7, 133.6, 132.3, 132.3, 131.4, 131.4, 128.6, 128.5, 128.3, 127.4, 127.1, 126.5, 125.7, 123.1, 123.1, 122.8, 63.9, 61.1, 61.1, 53.2, 51.6, 49.8; 31P NMR (242 MHz, CDCl3): δ 17.87; IR (KBr): ν 3063, 2947, 2830, 2684, 2199, 2097, 1911, 1825, 1710, 1632, 1520, 1431, 1330, 1099, 994, 801 cm−1. ESI-HR-MS. Calcd for C42H33BrO6P ([M+H]+): m/z 743.1193. Found: m/z 743.119.

Methyl 5-(4-chlorophenyl)-2-(2-methoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1h)

Yellow solid; yield 80%; mp 235–237°C; 1H NMR (400 MHz, DMSO-d6): δ 8.02 (d, J=7.6 Hz, 1H, ArH), 7.96 (t, J=7.6 Hz, 1H, ArH), 7.88 (t, J=7.2 Hz, 1H, ArH), 7.68 (d, J=7.6 Hz, 1H, ArH), 7.61 (t, J=7.2 Hz, 3H, ArH), 7.51–7.46 (m, 6H, ArH), 7.30–7.26 (m, 8H, ArH), 6.60 (m, 2H, ArH), 4.97 (s, 1H, CH), 4.22 (d, J=0.8 Hz, 1H, CH), 3.94 (t, J=2.0 Hz, 1H, CH), 3.32 (s, 3H, OCH3), 3.03 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 198.6, 198.5, 171.7, 171.7, 141.9, 141.4, 137.5, 135.0, 134.9, 133.7, 133.6, 131.7, 131.7, 131.6, 131.0, 128.4, 128.3, 127.5, 126.6, 123.7, 123.1, 121.2, 110.0, 64.3, 62.6, 62.5, 52.5, 51.7; 31P NMR (242 MHz, CDCl3): δ 18.82; IR (KBr): ν 3062, 2831, 2579, 2194, 1983, 1746, 1630, 1483, 1331, 1183, 1057, 918, 837, 760 cm−1. ESI- HR-MS. Calcd for C42H33ClO6P ([M+H]+): m/z 699.1698. Found: m/z 699.1725.

Methyl 5-(4-bromophenyl)-2-(2-methoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1i)

Yellow solid; yield 86%; mp 236–238°C; 1H NMR (400 MHz, DMSO-d6): δ 8.02 (d, J=7.6 Hz, 1H, ArH), 7.96 (t, J=7.2 Hz, 1H, ArH), 7.88 (t, J=7.2 Hz, 1H, ArH), 7.68 (d, J=7.6 Hz, 1H, ArH), 7.63–7.59 (m, 3H, ArH), 7.51–7.46 (m, 6H, ArH), 7.41 (d, J=8.0 Hz, 2H, ArH), 7.30–7.25 (m, 6H, ArH), 6.55 (m, 2H, ArH), 4.96 (s, 1H, CH), 4.19 (brs, 1H, CH), 3.94 (m, 1H, CH), 3.32 (s, 3H, OCH3), 3.03 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 198.6, 198.5, 171.7, 171.7, 141.9, 141.4, 137.5, 135.0, 134.9, 133.7, 133.6, 131.7, 131.7, 131.6, 131.0, 128.4, 128.3, 127.5, 126.6, 123.7, 123.1, 121.2, 110.0, 64.3, 62.6, 62.5, 52.5, 51.7; 31P NMR (242 MHz, CDCl3): δ 18.42; IR (KBr): ν 3063, 2947, 2831, 2103, 1786, 1747, 1710, 1632, 1481, 1332, 1099, 919, 873, 760 cm−1. ESI-HR-MS. Calcd for C42H33BrO6P ([M+H]+): m/z 743.1193. Found: m/z 743.1210.

Methyl 2-(2-methoxy-2-oxo-1-(triphenyl-λ5-phosphanylidene)ethyl)-5-(2-nitrophenyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1j)

Yellow solid; yield 92%; mp 224–226°C; 1H NMR (400 MHz, DMSO-d6): δ 8.00 (d, J=7.6 Hz, 1H, ArH), 7.95 (t, J=6.8 Hz, 1H, ArH), 7.85 (t, J=7.2 Hz, 1H, ArH), 7.78 (d, J=8.0 Hz, 1H, ArH), 7.68–7.62 (m, 5H, ArH), 7.54–7.50 (m, 7H, ArH), 7.36–7.31 (m, 6H, ArH), 7.08 (d, J=7.6 Hz, 1H, ArH), 5.11 (S, 1H, CH), 4.76 (d, J=0.8Hz, 1H, CH), 3.93 (d, J=1.2Hz, 1H, CH), 3.26 (s, 3H, OCH3), 2.91 (s, 3H, OCH3); 13C NMR (100 MHz, CDCl3): δ 199.8, 199.8, 171.4, 171.4, 149.6, 142.3, 142.2, 138.7, 138.6, 134.8, 134.6, 133.7, 133.3, 133.3, 133.3, 132.5, 131.6, 131.6, 128.6, 128.5, 127.8, 127.3, 126.3, 124.0, 122.8, 122.5, 62.1, 56.6, 56.6, 55.4, 51.6, 49.5; 31P NMR (242 MHz, CDCl3): δ 17.57; IR (KBr): ν 3063, 2946, 2831, 1979, 1745, 1637, 1522, 1434, 1268, 1183, 1066, 997, 857, 745 cm−1. ESI-HR-MS. Calcd for C42H33NO8P ([M+H]+): m/z 710.1938. Found: m/z 710.1944.

Ethyl 5-(2-chlorophenyl)-2-(2-ethoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1k)

Yellow solid; yield 80%; mp 198–200°C; 1H NMR (400 MHz, DMSO-d6): δ 7.98–7.92 (m, 2H, ArH), 7.88–7.84 (m, 1H, ArH), 7.68 (d, J=7.6 Hz, 1H, ArH), 7.61–7.58 (m, 3H, ArH), 7.50–7.45 (m, 6H, ArH), 7.37–7.32 (m, 6H, ArH), 7.23–7.19 (m, 3H, ArH), 6.94 (d, J=6.8 Hz, 1H, ArH), 5.30 (s, 1H, CH), 4.85 (s, 1H, CH), 3.89 (t, J=1.6 Hz, 1H, CH), 3.82 (m, 1H, CH), 3.67 (m, 1H, CH), 3.58 (d, J=6.8 Hz, 2H, CH), 0.71 (t, J=6.8 Hz, 3H, CH3), 0.64 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6): δ 198.7, 198.5, 170.7, 168.0, 141.9, 141.6, 138.9, 138.8, 136.3, 136.2, 135.6, 134.2, 133.6, 133.5, 132.3, 132.3, 132.1, 129.3, 129.1, 129.0, 129.0, 127.4, 127.1, 126.4, 123.4, 122.9, 121.5, 121.4, 63.6, 60.5, 57.9, 57.6, 52.7, 14.5, 13.7; 31P NMR (242 MHz, DMSO-d6): δ 18.25; IR (KBr): ν 3062, 2979, 2383, 2315, 1711, 1631, 1475, 1320, 1234, 1100, 867, 757 cm−1. ESI-HR-MS. Calcd for C44H37ClO6P ([M+H]+): m/z 727.2011. Found: m/z 727.203.

Ethyl 5-(2-bromophenyl)-2-(2-ethoxy-2-oxo-1-(triphenyl-λ5- phosphanylidene)ethyl)-1′,3′-dioxo-1′,3′-dihydrospiro [cyclopentane-1,2′-inden]-2-ene-4-carboxylate (1l)

Yellow solid, yield 75%; mp 200–202°C; 1H NMR (400 MHz, DMSO-d6): δ 7.97–7.91 (m, 2H, ArH), 7.86 (t, J=6.4 Hz, 1H, ArH), 7.67 (d, J=7.2 Hz, 1H, ArH), 7.60 (t, J=7.2 Hz, 3H, ArH), 7.47 (d, J=6.8 Hz, 6H, ArH), 7.42–7.33 (m, 7H, ArH), 7.22 (t, J=7.6 Hz, 1H, ArH), 7.14 (t, J=7.2Hz, 1H, ArH), 6.85 (d, J=7.2 Hz, 1H, ArH), 5.23 (s, 1H, CH), 5.00 (s, 1H, CH), 3.87 (s, 1H, CH), 3.80 (m, 1H, CH), 3.68 (m, 1H, CH), 3.58 (d, J=6.8 Hz, 2H, CH), 0.73–0.68 (m, 6H, CH3); 13C NMR (100 MHz, DMSO-d6): δ 198.7, 198.5, 170.6, 168.0, 142.1, 141.8, 139.4, 139.3, 137.3, 136.3, 136.1, 133.7, 133.6, 132.7, 132.3, 132.3, 129.4, 129.0, 128.9, 127.6, 127.4, 126.5, 125.5, 123.4, 123.0, 121.3, 121.2, 63.6, 60.7, 60.7, 60.5, 57.6, 52.8, 44.9, 43.6, 14.5, 13.7; 31P NMR (242 MHz, DMSO-d6): δ 18.79; IR (KBr): ν 3060, 2979, 1712, 1631, 1600, 1437, 1321 1277, 1185, 1102, 1020, 809, 757 cm−1. ESI-HR-MS. Calcd for C44H37BrO6P ([M+H]+): m/z 771.1506. Found: m/z 771.152.

Supporting information

Crystallographic data for 1h (CCDC 1488981), 1i (CCDC 1488982), and 1j (CCDC 1488983) has been deposited at the Cambridge Crystallographic Database Centre.

Funding source: National Natural Science Foundation of China

Award Identifier / Grant number: 21172190

Award Identifier / Grant number: 21572196

Funding statement: This work was financially supported by National Natural Science Foundation of China (Grant No. 21172190, 21572196) and the Priority Academic Program Development of Jiangsu Higher Education Institutions. We also thank the Analysis and Test Center of Yangzhou University for providing necessary instruments for analysis

Acknowledgments

This work was financially supported by National Natural Science Foundation of China (Grant No. 21172190, 21572196) and the Priority Academic Program Development of Jiangsu Higher Education Institutions. We also thank the Analysis and Test Center of Yangzhou University for providing necessary instruments for analysis.

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Received: 2016-7-27
Accepted: 2016-8-22
Published Online: 2016-9-24
Published in Print: 2016-10-1

©2016 Walter de Gruyter GmbH, Berlin/Boston

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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https://doi.org/10.1515/hc-2016-0123
Keywords for this article
diastereoselectivity; electron-deficient alkyne; 1,3- indanedione; phosphine; spiro[cyclopentane-1,2′-indene]
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Articles in the same Issue

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  2. Preliminary Communications
  3. Efficient synthesis of 4-amino-2,6-dichloropyridine and its derivatives
  4. Reactions of 3-arylmethylene-3H-furan(pyrrol)-2-ones with azomethine ylide: synthesis of substituted azaspirononenes
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