碱促进联烯酮与丙酮二羧酸酯反应制备 官能化的2-羟基间苯二甲酸酯
王强a,*, 赵新萍b
河南理工大学a化学化工学院;b医院 河南 焦作 454000;
通讯联系人:王强,副教授; Tel:0391-3987823; E-mail:wangqiang@hpu.edu.cn; 研究方向:有机合成与催化
摘要

发展了一种以碳酸钾为碱,在温和条件下,通过1,2-联烯酮与丙酮二羧酸二乙酯的串联反应高效合成取代2-羟基间苯二羧酸二乙酯类化合物的新方法。 在最优条件下,以73%~85%的收率成功合成了一系列的目标产物。 从机理上而言,该方法涉及了联烯酮与活泼亚甲基化合物的共轭Michael加成和酮的分子内羟醛缩合两个反应的串联组合。 与文献方法相比,该方法还具有简单的起始原料,极高的反应产率和方便的处理过程等优点。

关键词: 羟基间苯二甲酸酯; 联烯酮; 丙酮二羧酸酯; 串联反应
中图分类号:O625 文献标志码:A 文章编号:1000-0518(2018)06-0645-07
Synthesis of Functionalized 2-Hydroxyisophthalate via the Cascade Reactions of Allenic Ketones with Acetonedicarboxylate
WANG Qianga, ZHAO Xinpingb
aCollege of Chemistry and Chemical Engineering;
bHospital of Henan Polytechnic University,He'nan Polytechnic University,Jiaozuo,He'nan 454000,China;
Corresponding author:WANG Qiang, associate professor; Tel:0391-3987823; E-mail:wangqiang@hpu.edu.cn; Research interests:organic synthesis and catalysis
Abstract

A novel methodology for the synthesis of 2-hydroxyisophthalates through cascade reactions of 1,2-allenic ketones with ethyl acetonedicarboxylate using K2CO3 as the promoter under extremely mild conditions has been developed. Under optimal reaction conditions, a series of 2-hydroxyisophthalates derivatives were obtained with 73%~85% yield. The formation of the title compounds involves firstly a Michael addition of active methylene compounds and allenic ketone followed by its intramolecular condensation. Notable features of this protocol include simple starting materials, high yield, and easiness of handling.

Keyword: hydroxyisophthalate; allenic ketones; acetonedicarboxylate; cascade reaction

2-羟基间苯二甲酸酯结构单元存在于许多天然产物的结构中,是一类重要的有机中间体,广泛应用于有机合成和材料化学[1,2,3,4]。 有关2-羟基间苯二甲酸酯的合成报道很少,经典的合成方法是在强碱作用下,利用1,3-二羰基化合物与丙酮二羧酸酯的缩合反应[5,6]。 但这类反应存在一些缺点:如需要化学计量或过量的强碱(EtONa或NaOH)、有限的底物范围等,特别是这些反应的产率较低。 Takeuchi等[1,7]报道了利用有机金属催化的异恶唑与丙酮二羧酸酯的反应构建2-羟基间苯二甲酸酯结构单元,遗憾的是,该反应的产率依然很低。 因此,探索更加温和,高产率地制备2-羟基间苯二甲酸酯的制备方法仍然是很必要的(Scheme 1)。

Scheme 1 Previous synthetic approaches and our designed approach for the synthesis of 2-hydroxyisophthalates

近年来,联烯衍生物,尤其是缺电子联烯,因其多变的反应特点,得到了化学家的广泛关注[8,9,10,11,12]。 在这些缺电子联烯衍生物中,1,2-联烯酮是一个活泼性很强的亲电中心,它易与亲核试剂发生共轭加成反应生成含有 α, β-不饱和共轭体系的碳负离子中间体,这个中间体可以继续发生分子内环化反应,最终得到相应的碳环或杂环化合物。 麻生明等[13]首次报道了这类反应,他们利用联烯酮与丙二酸二乙酯的串联反应制备 α-吡喃酮衍生物。 最近,范学森等也对这类反应做了大量的研究,他们以联烯酮和活泼亚甲基化合物为起始原料,发展了一系列的多组分串联反应来构筑碳环和杂环化合物[14,15,16,17,18]。 在此基础上,我们报道了1,2-联烯酮与4-氯乙酰乙酸乙酯[19] α--羰基酯/二酮[20]的串联反应研究,合成一系列的新型的含氧杂环衍生物。 本文以1,2-联烯酮与丙酮二羧酸二乙酯的串联反应,制备了2-羟基间苯二甲酸二乙酯衍生物(Scheme 1),并通过核磁共振波谱(NMR)、质谱(MS)等光谱方法对其结构进行了表征。

1 实验部分
1.1 仪器和试剂

Bruker AV400型核磁共振仪(NMR,瑞士Bruker公司);Bruker microToF II型高分辨质谱仪(HRMS,德国Bruker公司)。 所有试剂均为市售分析纯,未经进一步纯化。 联烯酮参考文献[21,22]合成。

1.2 目标产物3的合成

以产物3a为例,在10 mL的圆底烧瓶中依次加入1-苯基-2,3-丁二烯-1-酮(1a,1 mmol)、丙酮二羧酸二乙酯(2, 1.0 mmol)、乙腈(5 mL)和无水碳酸钾(0.5 mmol),室温搅拌1 h。 反应完毕,加入饱和氯化铵淬灭反应,然后用乙酸乙酯萃取(5 mL×3),合并有机相,用饱和食盐水洗涤(10 mL×3)。 收集有机相,无水硫酸钠干燥,浓缩,乙酸乙酯乙酯/石油醚作为洗脱剂,薄层色谱快速柱层析得目标产物(3a,85%)。 利用上述方法也可以制备目标产物3b~3m。

产物3a 无色油状物(产率85%),洗脱剂,乙酸乙酯/石油醚(体积比1:30);1H NMR(400 MHz,CDCl3), δ:11.73(s,1H),7.26~7.37(m,5H),6.73(s,1H),4.46(q, J=6.8 Hz,2H),4.07(q, J=7.2 Hz,2H),2.52(s,3H),1.43(t, J=7.2 Hz,3H),0.91(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.9,168.4,159.7,145.6,142.3,140.5,128.1,128.0,127.7,124.1,117.2,115.5,61.8,61.1,22.6,14.2,13.4;HRMS(ESI)计算值C19H21O5[M+H]+:329.1389,实测值:329.1386。

产物3b 黄色油状物(产率73%),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.78(s,1H),7.23~7.12(m,3H),7.02~7.00(m,1H),6.57(s,1H),4.45(q, J=6.8 Hz,2H),3.98~3.91(m,2H),2.42(s,3H),2.07(s,3H),1.42(t, J=6.8 Hz,3H),0.75(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.1,168.8,159.5,145.6,142.2,141.1,135.0,129.4,128.0,127.4,125.1,124.0,118.6,114.2,61.6,61.0,21.3,19.8,14.2,13.0;HRMS(ESI)计算值C20H23O5[M+H]+:343.1545,实测值:343.1548。

产物3c 黄色油状物(产率75%),洗脱剂,乙酸乙酯/石油醚(体积比1:30);1H NMR(400 MHz,CDCl3), δ:11.78(s,1H),7.55(d, J=7.6 Hz,1H),7.29(t, J=7.2 Hz,1H),7.19~7.12(m,2H),6.55(s,1H),4.44(q, J=7.2 Hz,2H),4.04~3.91(m,2H),2.37(s,3H),1.40(t, J=7.6 Hz,3H),0.76(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.4,167.8,159.3,144.2,142.8,142.2,131.9,129.6,128.6,126.8,124.0,122.6,121.5,111.8,61.5,61.2,20.5,14.2,13.0;HRMS(ESI)计算值C19H20BrO5[M+H]+:407.0494,实测值:407.0490。

产物3d 黄色油状物(产率88%),洗脱剂,乙酸乙酯/石油醚(体积比1:30);1H NMR(400 MHz,CDCl3), δ:11.78(s,1H),7.26~7.22(m,1H),7.14~7.11(m,3H),6.72(s,1H),4.43(q, J=7.2 Hz,2H),4.08(q, J=7.6 Hz,2H),2.51(s,3H),2.35(s,3H),1.41(t, J=7.6 Hz,3H),0.94(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:170.1,168.3,159.7,145.7,142.3,140.2,137.7,128.7,128.5 128.0,125.1,124.1,114.7,61.8,61.1,22.8,21.3,14.1,13.5;HRMS(ESI)计算值C20H23O5[M+H]+: 343.1545,实测值: 343.1551。

产物3e 无色油状物(产率82%),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.75(s,1H),7.32~7.26(m,3H),7.18~7.15(m,1H),6.67(s,1H),4.43(q, J=7.2 Hz,2H),4.08(q, J=6.8 Hz,2H),2.47(s,3H),1.41(t, J=7.2 Hz,3H),0.94(t, J=6.8Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.5,168.2,159.7,143.9,142.5,142.3,133.9,129.3,128.1,127.7,126.3,123.9,116.6,116.2,61.8,61.3,22.3,14.2,13.4;HRMS(ESI)计算值C19H20ClO5[M+H]+:363.0999,实测值:363.0995。

产物3f 黄色油状物(产率85% ),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.74(s,1H),7.44(s,2H),7.21~7.20(m,2H),6.66(s,1H),4.43(q, J=6.8 Hz,2H),4.08(q, J=7.2 Hz,2H),2.47(s,3H),1.40(t, J=7.6 Hz,3H),0.94(t, J=7.2Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.4,168.2,159.7,143.7,142.6,142.5,131.0,130.6,129.6,126.7,123.9,122.0,116.7,116.2,61.8,61.3,22.3,14.2,13.5;HRMS(ESI)计算值C19H20BrO5[M+H]+:407.0494,实测值:407.0499。

产物3g 无色油状物(产率79%),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.78(s,1H),7.28~7.25(m,2H),6.90~6.87(m,2H),6.70(s,1H),4.24(q, J=7.2 Hz,2H),4.11(q, J=6.8 Hz,2H),3.80(s,3H),2.51(s,3H),1.41(t, J=7.2 Hz,3H),1.00(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:170.4,168.3,159.8,159.5,145.1,142.3,132.4,129.2,124.1,118.2,113.7,113.6,61.8,61.1,55.3,23.1,14.1,13.7;HRMS(ESI)计算值C20H23O6[M+H]+:359.1495,实测值:359.1499。

产物3h 黄色油状物(产率81%),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.76(s,1H),7.28~7.25(m,2H),7.05~7.01(m,2H),6.66(s,1H),4.42(q, J=7.6 Hz,2H),4.07(q, J=6.8 Hz,2H),2.48(s,3H),1.40(t, J=6.8 Hz,3H),0.94(t, J=7.6 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.8,168.2,163.7,161.3,159.7,144.3,142.4,136.43,136.39,129.8,129.7,124.0,117.2,115.4,115.1,114.9,61.8,61.2,22.6,14.1,13.5;HRMS(ESI)计算值C19H20FO5[M+H]+:347.1295,实测值:347.1291。

产物3i 黄色油状物(产率87%),洗脱剂,乙酸乙酯/石油醚(体积比1:20);1H NMR(400 MHz,CDCl3), δ:11.74(s,1H),7.48~7.45(m,2H),7.17~7.14(m,2H),6.64(s,1H),4.42(q, J=7.2 Hz,2H),4.06(q, J=6.8 Hz,2H),2.47(s,3H),1.40(t, J=6.8 Hz,3H),0.94(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.6,168.2,159.7,144.1,142.5,139.4,131.2,129.7,123.8,122.0,116.7,115.9,61.8,61.3,22.5,14.2,13.5;HRMS(ESI)计算值C19H20BrO5[M+H]+:407.0494,实测值:407.0501。

产物3j 黄色油状物(产率83%),洗脱剂,乙酸乙酯/石油醚(体积比1:10);1H NMR(400 MHz,CDCl3), δ:11.76(s,1H),7.62(d, J=8.0 Hz,2H),7.35(d, J=8.0 Hz,2H),6.61(s,1H),4.40(q, J=7.2 Hz,2H),4.13(q, J=7.2 Hz,2H),4.00(q, J=6.8 Hz,2H),2.42(s,3H),1.37(t, J=7.2 Hz,3H),1.21(t, J=7.6 Hz,3H),0.84(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:168.9,168.2,166.4,159.6,145.5,143.3,142.7,131.7,128.9,123.6,118.6,118.0,115.0,111.3,61.9,61.43,61.39,21.9,14.1,14.0,13.3;HRMS(ESI)计算值C22H25O7[M+H]+:401.1600,实测值:401.1503。

产物3k 黄色油状物(产率82%),洗脱剂,乙酸乙酯/石油醚(体积比1:30);1H NMR (400 MHz,CDCl3), δ:11.74(s,1H),7.62(d, J=8.4 Hz,2H),7.40(d, J=8.4 Hz,2H),6.67(s,1H),4.45(q, J=6.8 Hz,2H),4.04(q, J=7.2 Hz,2H),2.45(s,3H),1.42(t, J=6.8 Hz,3H),0.86(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:169.2,168.3,159.7,144.5,143.9,142.6,129.9,129.6,128.4,125.5,124.91,124.88,124.84,124.81,123.8,122.8,117.5,115.6,61.8,61.3,22.0,14.1,13.1;HRMS(ESI)计算值C20H20F3O5[M+H]+:397.1263,实测值:397.1265。

产物3l 黄色油状物(产率78%),洗脱剂,乙酸乙酯/石油醚(体积比1:25);1H NMR(400 MHz,CDCl3), δ:11.75(s,1H),6.85(s,1H),6.84(d, J=7.2 Hz,1H),6.80(d, J=7.2 Hz,1H),6.67(s,1H),4.36(q, J=7.2Hz,2H),4.05(q, J=6.8 Hz,2H),3.81(s,3H),3.80(s,3H),2.46(s,3H),1.34(t, J=6.8 Hz,3H),0.95(t, J=7.2 Hz,3H);13C NMR(100 MHz,CDCl3), δ:170.4,168.1,159.7,148.9,148.6,145.0,142.3,132.6,123.9,120.5,118.6,113.4,111.3,110.8,61.8,61.1,55.82,55.80,23.1,14.1,13.7;HRMS(ESI)计算值C21H25O7[M+H]+:389.1600,实测值:389.1604。

产物3m 无色油状物(产率84%),洗脱剂,乙酸乙酯/石油醚(体积比1:30);1H NMR(400 MHz,CDCl3), δ:11.89(s,1H),7.32~7.29(m,2H),7.23~7.19(m,3H),6.57(s,1H),4.47~4.40(m,4H),3.01~2.96(m,2H),2.91~2.87(m,2H),2.45(s,3H),1.43~1.38(m,6H);13C NMR(100 MHz,CDCl3), δ:170.0,168.7,160.1,145.6,142.5,141.3,128.4,128.3,126.1,124.2,61.6,61.5,37.5,36.7,32.5,14.3,14.2;HRMS(ESI)计算值C21H25O5[M+H]+:357.1702,实测值:357.1709。

2 结果与讨论
2.1 反应条件探索

为了优化反应条件,反应选择以1-苯基-2,3-丁二烯-1-酮(1a)和丙酮二羧酸二乙酯(2)为反应底物对该缩合反应进行了探究,考察了碱、溶剂和温度对反应的影响,具体结果如表1所示。 首先以K2CO3为碱,考察了不同的反应溶剂对目标产物的产率影响。 结果表明,极性较强的偶极非质子溶剂二甲基甲酰胺(DMF)、丙酮(acetone)、乙腈的效果明显优于极性较低的四氢呋喃(THF)和二氯甲烷(DCM)(Entries 1~5),这可能是由于无机碱在低极性溶剂里的溶解度太低所致。 在偶极非质子溶剂中,以乙腈的效果最好,以85%产率得到目标产物3a(Entry 5)。 接着我们以乙腈为溶剂,筛选了不同的无机碱对反应的影响。碱性较强的NaOH、碳酸铯、碳酸钠和碳酸钾的效果比较好(Entries 5,6,8,11),而碱性较弱的无机碱NaHCO3、LiOH、KF和有机碱三乙基胺(NEt3)的效果较差(Entries 7,9,10,12)。 另外,我们也发现升高反应温度,对反应产生不利影响,导致目标产物产率降低(Entry 13)。 因此优化后,制备取代2-羟基间苯二甲酸二乙酯的最佳的反应条件为:1,2-联烯酮(1 mmol),丙酮二羧酸二乙酯(1.0 mmol),无水碳酸钾(0.5 mmol),溶剂乙腈(5 mL),反应温度为室温,时间为1 h(Entry 5)。

表1 反应条件优化 Table 1 Optimization of the reaction conditions a
2.2 反应底物范围

在最优的反应条件下,我们考察了制备2-羟基间苯二甲酸二乙酯衍生物的底物范围。 从表2可以看出,对于1-芳基联烯酮而言,邻位取代底物的反应产率比间位和对位稍低(Entries 3,6,9),但均能得到良好的反应产率。 接着我们考察了联烯酮芳基上取代基的电子效应,如给电子取代基CH3、MeO和二甲氧基(Entries 2,4,7,12),以及吸电子取代基F、Cl、Br、CF3和CO2Et等(Entries 3,5,6,8~11)。 结果表明,取代基的电子效应对反应的产率没有显著的影响,无论是强吸电子的CF3还是强给电子的二甲氧基均能取得极好的产率。 另外,我们也发现1-烷基取代的联烯酮也能像1-芳基联烯酮一样顺利反应,以84%的高产率转化为相应的目标产物(Entry 13)。

表2 合成2-羟基间苯二甲酸乙酯的底物范围 Table 2 Substrate scope for the synthesis of 2-hydroxyisophthalates derivatives a
2.2 可能的反应机理

Scheme 2 Proposed reaction mechanism for the formation of compound 3a

基于上述实验结果和相关文献报道[14,15,16,17,18],我们提出以下可能的反应机理过程(Scheme 2):首先,碱脱去丙酮二羧酸二乙酯(2)中的一个活泼亚甲基的质子得到碳负离子中间体A,A与联烯酮(1a)中联烯单元的中间碳原子发生共轭加成得中间体B,B发生质子转移得到另一个负离子中间体C,接着中间体C发生分子内的羟醛缩合得D,D通过脱水、异构化等一系列反应最终生成目标产物2-羟基间苯二甲酸酯衍生物3a。

3 结 论

开发了一种利用碳酸钾为碱的联烯酮与丙酮二羧酸二乙酯的串联环化反应制备2-羟基间苯二甲酸酯衍生物的方法。 本文采用易制备的链状化合物联烯酮和便宜的丙酮二羧酸二乙酯为原料,在温和反应条件下,高效制得芳环衍生物。 与文献方法相比,该过程具有操作简便,易处理,反应快速和产率高的优点,是对2-羟基间苯二甲酸酯类化合物制备方法的有效补充。

辅助材料(Supporting Information)[目标产物的1H、13C NMR谱图]可以免费从本刊网站(http://yyhx.ciac.jl.cn/)下载。

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