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JJCJordan Journal of Chemistry Vol. 7 No.2, 2012, pp. 125-139Nicotine-Based Ionic Liquid as a Green and Recyclable Catalyst forMorita Baylis-Hillman ReactionAhmed Ali Hullio ∗ , G.M MastoiDr. M.A Kazi Institute of chemistry, University of Sindh Jamshoro-76080, PakistanReceived on Dec. 18, 2011 Accepted on May 24, 2012AbstractNicotine-based task specific ionic liquid has been used as an alternative green andrecyclable nucleophilic reagent for Morita–Baylis–Hillman reaction. The potential of proposednew methodology has been applied on reported work performed under ordinary routinechemistry. The results obtained prove the worth of new protocol with numerous advantages overthe conventional method.Keywords: Nicotine-based task specific ionic liquid; Baylis-Hillman reaction;Recyclable reagent.IntroductionThe Baylis-Hillman reaction is an organic reaction between aldehydes andactivated alkenes like α,β-unsaturated carbonyls or imines catalyzed by nucleophillicorgano reagent called DABCO (1,4-diazabicyclo[2.2.2] octane) to give correspondingallylic alcohols [1] . The key features of this reaction include carbon-carbon bondformation, densely functionalized product and creation of an asymmetric centre. Theseremarkable aspects of Baylis-Hillman reaction has drawn much attention of the organicchemists and has become one of the most demanding research areas in currentorganic chemistry. Apart from this, it has many other advantages like atomic economy,nonmetal catalysis, mild conditions, and compatibility of multiple functional groups.The mechanistic studies of the reaction as described by wikipedia [2] suggeststhat nucleophilic addition of DABCO 2 onto the α,β-unsaturated ketone 1 gives aresonance-stabilized anion intermediate 3, which in situ adds to the aldehydeproducing another intermediate called the keto-alcohol 4. Subsequent elimination ofthe DABCO gives the desired allylic alcohol 5 (scheme 1).∗Corresponding author: E-mail: ahmedalihullio@yahoo.com; Tel: (+92-22) 2771681-90-Ext: 2004.Fax: (+92-22) 2771372125

Scheme 1This reaction is usually carried out under homogeneous conditions in thepresence of organic Lewis base catalysts such as DABCO, [3] DMAP, [4] DBU, [5] [6]PPh 3[7]PBu 3 PPh 2 Me, [8] and imidazoles [9] . In most cases, stoichiometric or excess amount ofLewis bases is required to make reactions faster and improve the product yields. It istherefore of interest to develop recyclable and reusable Baylis-Hillman catalysts, whichwill make the reaction more atom-economic and efficient. In pursuance of this objectCorma et al [10] investigated the use of commercially available poly-DMAP as therecyclable Baylis-Hillman catalyst. The heterogeneous catalyses have been proved tobe inefficient, because they generally take several days to achieve acceptable yields.Contrary to this, Baylis Hillman reaction under homogeneous conditions is shown tohave faster rate and higher yields compared to the reaction under heterogeneousconditions. [11] Further the PEG-bound alkyl diphenylphosphines has been reported asa recyclable Baylis-Hillman catalysts leading to enhanced rate of reaction. [12]The task specific ionic liquids are special class of ionic liquids based onimidazolium cation to which an organocatalyst is attached with two or more carbonspacings. Such systems have been used as green version of organocatalyst orsolvents-cum-organocatalyst leading to faster rates and excellent yields and efficientrecycling. [13,14] In case of DABCO-catalysed Baylis-Hillman coupling, earlier work hasshown that ionic liquid can accelerate the reaction when used as a reaction media. [15,16]More important contribution came from Xueling Mi et al who designed theQuinuclidine-task specific ionic liquid for Morita-Baylis-Hillman reactions to beconducted under homogenous conditions. [17]R CHO +1.5 eqR 1Bu0.3 eqNNBF 4HNN2 eq MeOH, r.t, 0.5 - 48hROHR 1Scheme 2Quinuclidine-based task specific ionic liquid seems to be pertinent for Morita-Baylis-Hillman reactions but this reagent involves lengthy and expensive syntheticscheme.126

Task specific ionic liquids have been designed and applied successfully withexcellent procedural advantages. [18] Recently our group has contributed very significantwork on task specific ionic liquids and interestingly have introduced a novel concept ofmultipurpose ionic liquids. in contrast to task specific ionic liquids which are designedfor one specific reaction, our newly introduced “Multipurpose” ionic liquids can beapplied to variety of diversified organic transformations. [19-21] As a continuation ofworldwide work on Baylis-Hillman reactions [22-25] and applications of ionic liquids (ILs),we are introducing a nicotine-based nucleophilic task specific ionic liquid as an easilyaccessible, green and recyclable catalyst for Baylis-Hillman reactions. The basicoperation is based on the biphasic strategy, i.e., homogeneous reaction andheterogeneous separation of product and catalyst. It is the first example of usingnicotine-based ionic liquid as a Baylis-Hillman catalyst as an efficient and recyclablegreen catalyst.R 1O+.. NILN HexylR 1ONILOH R 2R 1OHONR 2ILNTf 2NTf 2proton trasnferOOHR 1 R 2+.. NILN HexylScheme 3Nicotine is naturally available compound and its simple structural manipulationleads to a highly useful ionic liquid which can act as a multipurpose nucleophilicsolvent. Since the nitrogen in pyridine has lower nucleophilicity as compared to that ofDABCO, this seems to imply that nicotine-based ionic liquid would be comparativelyincompetent. However the formation of polar intermediates throughout the Baylis-Hillman reaction, suggests that its execution in a highly polar and ionic solvent will befavorable. Higher yields in little reaction time can be appreciably achieved byconducting such reaction under ionic liquids conditions.Every research work on Baylis-Hillman reaction by any groups claim theexcellent results in terms of yields but high cost and laborious procedure make theirreported system less attractive. The ionic liquids either used as solvents ororganocatalyst have facilitated the operational methods involving organictransformations. In addition to this relatively rapid reaction rates and higher yields arekey merits associated with ionic liquids. In case of nicotine-based nucleophilic taskspecific ionic liquid, although nucleophilicity of nitrogen in pyridine is many times lower127

than DBU, still the reaction is favorable due to stabilization of polar intermediate inhighly polar condition furnished by ionic liquid.ExperimentalGeneralAll the reagents and solvents were pure and of analytical grade chemicalspurchased from Aldrich and were used without further purification. Melting/boilingpoints were determined with a Buchi 510 melting point apparatus (Flawi/SG,Switzerland) and are uncorrected. Electron impact (EIMS) mass spectra weredetermined with a Finniggan MAT-312 (Bremen, Germany), Vrain MAT-112 (Bremen,Germany) double focusing mass spectrometer connected to a PDP 11/34 (DEC)computer system. The 1 H-NMR spectra were recorded in CD 3 OD and CDCl 3 withBruker AM 300 and 400 spectrometers (Rheinstetten-Forchheim, Germany) operatingat 300 and 400 MHz, respectively. 1 H-NMR chemical shifts are reported in δ (ppm) andcoupling constants in Hz. The purity of the products was checked on TLC plates(Merck, Darmstadt, Germany), coated with silica gel PF 254 and the spots werecharacterized with UV light at 254 and 366 nm and by spraying with ninhydrin andiodine tank.Procedure for preparation of Nicotine based ionic liquidPreparation of Compound 4bThe nicotine 4a (10 g, 0.079 mole) and benzyl bromide (13.5 g, 0.079 mole)were dissolved in 60 ml acetonitrile in 150 ml round bottom flask. The reaction mixturewas refluxed and progress of reaction was monitored by TLC analysis. The reactionwas completed during 15 hrs. After cooling the reaction mixture, removal of the solventin vacuo afforded 19.32 g (94%) of compound 4b as a pale orange salt. The ioniccompound 4b was characterized by 1 HNMR and 13 CNMR.1 HNMR (400MHz, CDCl 3 ) (ppm) 7.17 – 7.32 (m, 5H), 6.17(s, 2H), 7.24 – 9.37(m, 4H),2.18 (s, 3H), 2.86(t, J = 7.35 Hz, 1H), 1.50 – 2.06 (dt, J = 7.35 Hz, J = 3.8 Hz, 2H),1.80 – 206 (tt, J = 7.3 Hz, J = 3.8 Hz, 2H), 2.46 – 3.23 (t, J = 6.51 Hz, 2H) 13 CNMR(300MHz, CDCl 3 ) (ppm) Pyrrolidine 93.23(N-CH 3 ), 54.32(CH 2 ), 22.68(CH 2 ),34.54(CH 2 ), 69.20(CH) Pyridine 132.09(C), 137.84(CH), 143.58 (CH), 124.29(CH),140.11(CH), 62.33(N-CH2) Phenyl 134.69 (C), 128.23 (CH), 128.25(CH), 127.00(CH),128.25(CH), 128.23(CH) HRMS(EI) C 17 H 21 N 2 Br calcd. 333.362; found 333.371Preparation of Compound 4cThe Bromide salt 4b (19.32 g, 0.058 mole) and hexyl iodide (12.30g, 0.058mole) were dissolved in 60 ml acetonitrile in 150 ml round bottom flask. The reactionmixture was refluxed for 20 hrs. After completion of reaction, as confirmed by TLC,128

yellow crystalline product was filtered from reaction mixture 0 o C, washed with acetoneand recystallised twice from H 2 O/acetone (15:85). The salt was dried in desiccator togive 40.04 g (95%) of desired product 4c.1 HNMR (400MHz, CDCl 3 ) (ppm) 0.88 – 1.74(m, 11H), 3.11 – 3.32(t, J = 7.00 Hz, 2H),7.17 – 7.32 (m, 5H), 6.17(s, 2H), 7.24 – 9.37(m, 4H), 3.11 (s, 3H), 4.55 (t, J = 9.00 Hz,1H), 2.20 – 2.27 (dt, J = 9.00 Hz, J = 7.4 Hz, 2H), 2.20 – 2.27 (tt, J = 7.95 Hz, J = 7.45Hz, 2H), 3.64 – 3.71 (t, J = 7.95 Hz, 2H) 13 CNMR (300MHz, CDCl 3 ) (ppm) Pyrrolidine48.77(N-CH 3 ), 66.26(CH2), 20.75(CH2), 27.63(CH2), 81.01(CH) N-Hexyl 59.79(CH2),23.93(CH2), 26.26(CH2), 31.20(CH2), 22.35(CH2), 13.80(CH3), Pyridine 138.61(C),131.06(CH), 143.90 (CH), 123.55(CH), 138.35(CH), 62.33(N-CH2) Phenyl 134.69 (C),128.23 (CH), 128.25(CH), 127.00(CH), 128.25(CH), 128.23(CH) HRMS (EI) C 23 H 34N 2 Br I calcd.545.532; found 545.534.Preparation of Compound 4dThe salt 4c (30.04 g, 0.055 mole) and triphenyl phosphine (14.42 g, 0.055 mole)were dissolved in 65 ml methanol in 150 ml round bottom flask. The reaction mixturewas refluxed for 6 hrs. After completion of reaction as indicated by TLC, the solventwas concentrated under vacuo. The residue was extracted with (5x10 ml) dimethylether. The ether was concentrated and ether residue was washed with water and driedwith Na 2 SO 4 then removed completely to give compound 4d 19.72 g (92%).1 HNMR (400MHz, CDCl 3 ) (ppm) 0.88 – 1.74(m, 11H), 3.11 – 3.32(t, J = 7.00 Hz, 2H),9.48(s, 1H), 8.54(d, J 4.85Hz, 1H), 6.76(m, 1H), 8.81(m, 1H), 3.11 (s, 3H), 4.55 (t, J =9.00 Hz, 1H), 2.20 – 2.27 (dt, J = 9.00 Hz, J = 7.4 Hz, 2H), 2.20 – 2.27 (tt, J = 7.95 Hz,J = 7.45 Hz, 2H), 3.64 – 3.71 (t, J = 7.95 Hz, 2H). 13 CNMR (300MHz, CDCl 3 ) (ppm)Pyrrolidine 48.77(N-CH 3 ), 66.26(CH2), 20.75(CH2), 27.63(CH2), 81.01(CH) N-Hexyl59.79(CH2), 23.93(CH2), 26.26(CH2), 31.20(CH2), 22.35(CH2), 13.80(CH3), Pyridine124.45(C), 141.13(CH), 145.69 (CH), 118.05(CH), 129.19(CH) HRMS(EI) C 17 H 30 N 2 Icalcd. 389.434; found 389.438.Preparation of Compound 4eLithium triflimide (14.40 g, 0.050 mmol) of was dissolved in 25 mL of water. Andin a separate flask, 19.72 g (0.051 mol) of iodide salt 4d was dissolved in 65 mL ofwater. Both solutions were heated to 70 °C and then combined. The combined solutionwas allowed to cool to room temperature while stirring was continued for 3 h. The topaqueous layer was decanted and extracted with methylene chloride (2 × 5 mL). Thesewashes were combined with the original remaining ionic liquid layer and washed withwater (2 × 5 mL). The organic layer was filtered through a short plug of basic aluminaand the solvent removed under vacuo. The residue was dried on a vacuum lineovernight to afford 4e 0.2193 g (72%) as a pale yellow liquid. Its purity was checked by129

oth 1 HNMR and 13 CNMR as well as elemental analysis. HRMS (FAB) C 19 H 30 N 3 O 2 F 6S 2 Li calcd. 563.434, found 563.434General Procedure. To the solution of 4e (0.080 mg, 0.15 mmol) in CH 3 OH (41 , 2.0equiv) were added aldehyde (0.5 mmol) and activated alkene (0.75 mmol). Theresulting solution was stirred at ambient temperature and monitored by TLC. After theindicated reaction time, the solution was concentrated and the residue was extractedwith diethyl ether. The ether extracts were rotary-evaporated, and the crude productwas purified by flash chromatography on silica gel to afford the desired product. Theremaining layer was further vacuumed to dryness and the resulting catalyst wasreused directly for the next run. The reactions using the recycled catalyst wereconducted in a similar manner.Results and DiscussionHandy et al have reported Nicotine derived ionic liquid (Figure1) andinvestigated its potential as a nucleophillic ionic liquid solvent for acylation of differentalcohols with acetic anhydride. [26]N HexylNfT 2N4eFigure 1The nicotine based task specific ionic 4e was synthesized as shown in scheme4. In theory, there are three possible types of room temperature ionic liquids (RTILs)available from nicotine: two different monocations (1 and 2) and one dication 3 (Figure2). From the two possible monocationic species only 2 has nucleophilic nitrogen toperform catalysis.INNHexNNNHexII Hexyl1 2 3INHexFigure 2Selective preparation of nucleophillic nicotine ion 2 is not quite simple. Theprocedure requires for selective alkylation of the pyrrolidine moiety as reported by130

Shibagaki. [27] The procedure starts with regioselective N-benzylation of pyridine ofnicotine 4a with benzyl bromide to give 4b. The bromide salt 4b is then treated withhexyl iodide for N-alkylation of pyrrolidine to form dicationic salt 4c. Treatment of N-benzyl-N'-alkylnicotinium dihalides 4c with Ph 3 P provided a synthetic route to N'-hexylnicotinium salts 4d with nucleophilic pyridine. The final iodide salt 4d was highlyviscous liquids at room temperature. The anionic metathesis of iodide ion in salt 4dwith triflimide produced was relatively less viscous liquid quantitatively. [28]N4aNBnBrBrNNCH 2 -Ph 4bHexyl-IBrINHexylN4cCH 2 -Ph_Ph 3 PPh 3 P CH 2 -PhBrN4dIN HexylLiNfT 2NN HexylNfT 24eScheme 4The preparation of the triflimide salts was achieved by anion metathesis withlithium triflimide in distilled water. The resulting ionic liquid was characterized by 1 HNMR and 13 C NMR, and MS. Following the anion exchange, Nicotine-based ionic liquid4e was isolated by extraction with methylene chloride and then washed with water.The choice of an ionic liquid with the NTf 2 anion followed from the its ability to depressthe melting point of salt, its hydrophobic character to resist moister, its air stability andweak coordination character. The ionic liquids containing this anion are known to bemore chemically and thermally stable than the ionic liquids with BF 4 - or PF 6 - anions,which undergo hydrolysis with formation of hydrogen fluoride. NTf 2 anions also havelow viscosity which considerably facilitates manual operation. [29,30]Catalytic Conditions. The Baylis-Hillman reaction of benzaldehyde and methyl acrylatewas selected as the model reaction for subsequent screening. The reaction wasconducted in the presence of Nicotine-based IL at room temperature with (2.0 equiv) ofmethanol (Scheme 2). Initially the yield was moderate (Table 1, entry 4). Effect ofprotic solvents especially methanol for promoting the Baylis-Hillman reactions isestablished by various research groups. Protic solvent plays a dominant role inaccelerating the reaction, probably via hydrogen bonding131

OTosNHH OPPh 2RFigure 3The nicotine-based ionic liquid was quite stable under the Baylis-Hillmanreaction conditions. These facts and observations encouraged us to check its potentialfor other substrates. Baylis-Hillman reactions of various aldehydes were examined withmethyl acrylate, acrylonitrile and cyclohexenone. The potential of present system wasalso investigated for aryl tosylimines which on reaction with different acceptors gavebeta-amino enones.ApplicationsThe optimal conditions developed above were employed for Nicotine-basedTSIL-catalyzed Baylis-Hillman reactions of acrylates with a variety of aldehydes. All ofthe test reactions were conducted at room temperature (Table 1). The data in (Table 1)reveals that all types of aldehydes both aliphatic and aromatic aldehydes exhibitedvery efficient Baylis-Hillman reactions with acrylates in the presence of 0.3 equiv of 4e,giving the corresponding Baylis-Hillman adducts in good to excellent yields (51-87%).132

Table 1: Baylis-Hillman Reactions of aldehyde (1.0 equiv) and Acrylates (1.5 equiv)by Nicotine-based task specific ionic (0.3 equiv) in 2.0 equiv of Methanol at roomtemperatureR 1 CHO +OHCO 2 Me Nicotine-based TSIL(0.3 eqv)CO 2 MeRCH 1 3 OH (2.0 equiv)Entry R 1 Time(h) Yield a (%)1 n-C 3 H 7 10 512 i-C 4 H 9 10 733 n-C 6 H 13 10 744 Ph 6 595 p-ClPh 5 776 p-CH 3 Ph 8 657 p-iPrPh 10 638 p-NO 2 Ph 1 829 o-NO 2 Ph 0.5 7510 m-NO 2 Ph 1 8011 2-pyridyl 0.5 8112 3-pyridyl 1 7913 4-pyridyl 0.5 8514 2-furfuryl 1 87Isolated Yield.All compounds gave correct spectral data( 1 HNMR, 13 CNMR)The analogous reactions of acrylonitrile were also investigated. Again, highyields were achieved in shorter reaction time. As shown in table 2, the Nicotine-basedTSIL catalyst was highly effective for all the substrates tested. It was found that thereaction of p-methoxybenzaldehyde, which is usually quite an inert substrate, couldprovide a fairly good yield (58%, entry 4) of isolated Baylis-Hillman adduct under thepresent conditions, demonstrating the good activity of the nicotine-based ionic liquidcatalyst.133

Table 2: Baylis-Hillman Reactions of aldehyde (1.0 equiv) and Acrylates (1.5 equiv) byNicotine-based task specific ionic (0.3 equiv) in 2.0 equiv of Methanol at roomtemperatureR 1 CHO +CN OHNicotine-based TSIL(0.3 eqv)CNRCH 1 3 OH (2.0 eqv)Entry R 1 Time(h) Yield a (%)1 Ph 6 802 P-ClPh 6 793 P-CH 3 Ph 8 724 P-CH 3 OPh 18 585 P-NO 2 Ph 0.5 806 2-pyridyl 0.5 827 Piperonal 1 748 Furfuraldehyde 1 78a Isolated yieldsAll compounds gave correct spectral data( 1 HNMR, 13 CNMR)Cyclic enones are poor Michael acceptors, and consequently the Baylis-Hillmanreactions involving cyclic enones were usually observed to be sluggish under normalconditions. A variety of catalysts have therefore been employed for this kind of reactionin order to improve its efficiency. In our study, we found that the reactions of 2-cyclohexenone proceeded quite effectively using 4e as catalyst under the conditionsmentioned above, providing the Baylis-Hillman adducts in fair to high yields (Table 3).Minor amount of aldol products was also isolated in some cases probably due to therelatively strong basicity of the catalyst.134

Table 3: Baylis-Hillman Reactions of aldehyde (1.0 equiv) and Cyclohexenone (1.5equiv) by Nicotine-based task specific ionic (0.3 equiv) in 2.0 equiv of Methanol atroom temperature.R 1 CHO +ONicotine-based TSIL(0.3 eqv)CH 3 OH (2.0 eqv)R 1OHOEntry R 1 Time(h) Yield a (%)1 Ph 10 622 p-ClPh 10 763 p-CH 3 Ph 18 324 p-NO 2 Ph 5 585 2-pyridyl 40 23a Isolated yields.All compounds gave correct spectral data( 1 HNMR, 13 CNMR)Nicotine-based TSIL catalysed Baylis-Hillman reaction of imines was examinedwith methyl vinyl ketone and methyl acrylate with aryl tosylimines 11 were used as theelectrophiles (Table 4). The proposed reagent proved its worth in accomplishing theBaylis-Hillman reaction of various tosylimines with methyl acrylates. Table 4 showsthat lower to modest yields were obtained. Our educated guess suggests that theyields can be enhanced by bringing the reaction to higher temperature.135

Table 4: Baylis-Hillman Reactions of aryl tosylimines (1.0 equiv) and methyl acrylate(1.5 equiv) by Nicotine-based task specific ionic (0.3 equiv) in 2.0 equiv of Methanol atroom temperatureONHTsONTs+ OMeAr OMeAr HEntry Ar Time[h] Yield[%]1 C 6 H 5 30 402 3-CH 3 C 6 H 4 21 303 3- (OCH 3 )C 6 H 4 21 314 4-ClC 6 H 4 13 265 3-ClC 6 H 4 12 236 3-BrC 6 H 4 12 287 1-Naphthyl 20 208 2-Thiophenyl 28 259 3-Furyl 26 18Isolated Yield.All compounds gave correct spectral data( 1 HNMR, 13 CNMR)Various aryl tosylimines were also subjected to Baylis-Hillman reaction with 2-butenone. Almost similar trend in yields and rates of reaction was observed as inabove case (Table 5).136

Table 5: Baylis-Hillman Reactions of aryl tosylimines (1.0 equiv) and methyl vinylketone (1.5 equiv) by Nicotine-based task specific ionic (0.3 equiv) in 2.0 equiv ofMethanol at room temperatureNHTsONTsO+ ArAr HEntry Ar Time[h] Yield[%]1 C 6 H 5 20 412 p-MeC 6 H 4 20 433 p-EtC 6 H 4 30 526 p-FC 6 H 4 13 747 p-ClC 6 H 4 18 628 p-BrC 6 H 4 14 749 m-FC 6 H 4 19 2110 m-ClC 6 H 4 12 5211 p-NO 2 C 6 H 4 8 5312 m-NO 2 C 6 H 4 8 43Isolated Yield.All compounds gave correct spectral data( 1 HNMR, 13 CNMR)Our present observations indicate that the Nicotine-based TSIL is an excellenthomogeneous catalyst for Baylis-Hillman reactions. And more importantly, the use ofthe ionic liquid-linked catalyst can facilitate easy product separation and reuse of thecatalyst. After each run, the product was readily separated by extraction with diethylether, and the ionic liquid residue, i.e., the catalyst, can then be used directly for nextrun without further treatment. It was found that the ionic liquid-supported catalyst couldbe recycled for at least six times without too much loss of its activity (Table 6).RecyclingThe thermal stability and nonvolatile nature of ionic liquids make them viablefor recycling. Homogenous catalysis and easy recovery of product and ionic liquidprevent the loss of amount of ionic liquid. Generally, the reactions demonstratedreasonable efficiency and gave good yields in comparison with the cases where othercommon homogeneous or heterogeneous catalysts were used. The ionic liquid-boundcatalyst can be readily recovered from the reaction mixture and be reused severaltimes without much loss of its activity, thus providing a reasonably efficient alternativereagent for the Baylis-Hillman reactions to be carried out under environmentally morefriendly conditions.137

Our recycling study suggest that nicotine based ionic liquids can be recycledaround dozen times without any significant loss of the activity of the reagent. Therecycling studies were done with Baylis-Hillman reactions of p-nitrobenzaldehyde (1.0equiv) and methyl acrylates (1.5 equiv) by Nicotine-based task specific ionic (0.3equiv) in 2.0 equiv of Methanol at room temperature. The results obtained are shownin table 6. Recycling from one to six gave invariably same yields under same condition.Detectable loss in activity can be seen from recycling number ten and onwards.Table 6: Recycling profile for Nicotine-based task specific ionicNumber ofRecycling 1 2 3 4 5 6 7 8 9 10 11 12Isolated Yield82 82 81 81 81 80 80 79 77 74 72 69ConclusionIn summary, we in the present work have investigated a range of Baylis-Hillmanreactions using the Nicotine-based TSIL as a new catalyst. Generally, the reactionsdemonstrated good efficiency and gave better yields in comparison with the caseswhere other common homogeneous or heterogeneous catalysts were used. The ionicliquid catalyst can be readily recovered from the reaction mixture and be reusedseveral times without much loss of its activity providing environmentally more friendlyconditions.AcknowledgmentAuthors gratefully acknowledge the financial support provided by University ofSindh Jamshoro and H.E.J International centre for chemical and biological sciences forspectroscopic facilities.References[1] Park, K. S.; Kim, J.; Choo, H.; Chong, Y., Synlett, 2007, 395.[2] http://en.wikipedia.org/wiki/Baylis%E2%80%93Hillman_reaction[3] Cai, J.; Zhou, Z.; Zhao, G.; Tang, C., Org. Lett., 2002, 4, 4723.[4] Ito, H.; Takenaka, Y.; Fukunishi, S.; Iguchi, K., Synthesis, 2005, 3035.[5] You, J.; Xu, J.; Verkade, J. G., Angew. Chem., 2003, 115, 5208.[6] Shi, M.; Liu, Y.-H., Org. Biomol. Chem., 2006, 4, 1468.[7] Yu, C.; Hu, L., J. Org. Chem., 2002, 67, 219.[8] Mi, X.; Luo, S.; Cheng, J.-P., J. Org. Chem., 2005, 70, 2338.[9] McDougal, N. T.; Schaus, S. E., J. Am. Chem. Soc., 2003, 125, 12094.[10] Matsui, K..; Takizawa, S.; Sasai, H., Synlett, 2006, 761.[11] Corma, A.; Garci´a, H.; Leyva, A. Chem. Commun., 2003, 2806.[12] (a) Yu, C.; Liu, B.; Hu, L., J. Org. Chem. 2001, 66, 5413. (b) Yu, C.; Hu, L., J. Org. Chem.2002, 67, 219. (c) Cai, J.; Zhou, Z.; Zhao, G.; Tang, C., Org. Lett., 2002, 4, 4723.[13] Mi, X. L.; Luo, S. Z.; He, J. Q.; Cheng, J.-P., Tetrahedron Lett., 2004, 45, 23, 4567.138

[14] For reviews, see: (a) Wasserscheid, P.; Keim, W., Angew. Chem., Int. Ed., 2000, 39,3772. (b) Welton, T., Chem. Rev., 1999, 99, 2071. (d) Wilkes, J. S., Green Chem., 2002,4, 73. (c) Hullio, A.A.; Mastoi, G.M., Oriental Journal of Chemistry, 27 (4), 2011, 1591.[15] Sheldon, R., Chem. Commun., 2001, 2399.[16] Rosa, J. N.; Afonso, C. A. M.; Santos, A. G., Tetrahedron, 2001, 57, 4189. For otherlater examples, see: (a) Hsu, J.-C.; Yen, Y.-H.; Chu, Y.-H., Tetrahedron Lett., 2004, 45,4673. (b) Kim, E. J.; Ko, S. Y., Helv. Chim. Acta, 2003, 86, 3, 894.[17] Aggarwal, V. K.; Emme, I.; Mereu, A., Chem. Commun., 2002, 1612.[18] Hullio, A.A.; Mastoi, G.M., Oriental Journal of Chemistry, 27(4), 2011, 1591[19] Hullio, A.A.; Mastoi, G.M., Asian journal of chemistry, 23(12), 2011, 5411.[20] Hullio, A.A.; Mastoi G.M., Iranian Journal of Catalysis, 1(2), 2011, 79.[21] Hullio, A.A.; Mastoi, G.M., Chinese Journal of chemistry, 2012, (In Press)[22] Mi, X.; Luo, S.; Cheng, J.-P., J. Org. Chem., 70, 2005, 2338-2341[23] Luo, S. Z.; Zhang, B. L.; He, J. Q.; Janczuk, A.; Wang, P. G.; Cheng, J.-P., TetrahedronLett., 43, 2002, 7369.[24] Luo, S. Z.; Wang, P. G.; Cheng, J.-P., J. Org. Chem., 69, 2004, 555.[25] Luo, S. Z.; Mi, X. L.; Wang, P. G.; Cheng, J.-P., Tetrahedron Lett., 45, 2004, 5171.[26] Gatri, R.; El Gaied, M. M., Tetrahedron Lett,. 43, 2002, 7835.[27] Handy, S. T., Eur. J. chem., 9(13), 2003, 2938.[28] Shibagaki, M.; Matsushita, H.; Kaneko, H., Heterocycles, 20, 1983, 497.[29] (a) Gathergood, N.; Scammells, P. J., Aust. J. Chem., 55, 2002, 557; (b)Demberelnyamba, D.; Shin, B. K.; Lee, H., Chem. Commun., 2002, 1538.[30] Bonhote, P.; Dias, A.-P.; Papageorgiou, N.; Kalyanasundaram, K.; Gratzel, M., Inorg.Chem., 35, 1996, 1168.139