祝小艷,聶 晶
(天津大學理學院,天津300072)
偶氮化合物在有機化學領域有著非常重要的作用,不僅可以作為含氮親電試劑用于有機合成[1],也是一類用途廣泛的自由基引發(fā)劑[2]。偶氮化合物可以作為食品色素、染料等,還可以作為藥物前體,在人體酶的作用下釋放出有藥物活性的物質[3]。然而,由于脂肪族偶氮化合物受熱易分解[4],高效簡便地合成此類化合物的方法一直受到化學家的關注。已有的報道大部分是利用芳基重氮鹽結合非活潑的烯烴以及烯烴衍生物,通過自由基反應來獲得脂肪族偶氮化合物[5-8]。通過甲醛單取代腙與其它親電底物反應是合成脂肪族偶氮化合物的另一條有效途徑,但相關報道還很少[9]。近年來,Lassaletta小組利用甲醛N-叔丁基腙與α-羰基酸酯及硝基烯烴的不對稱加成反應,得到一系列手性脂肪族偶氮化合物[10,11]。然而,通過甲醛單取代腙與酮亞胺的加成反應來合成脂肪族偶氮化合物的反應尚未見文獻報道。
鑒于此,作者在堿作用下通過甲醛N-叔丁基腙與環(huán)狀N-?;獊啺返挠H核加成反應,合成了新型三氟甲基取代偶氮化合物。由于所得偶氮化合物在酸性條件下容易發(fā)生異構化反應形成腙,它是重要的合成中間體,可以轉化為相應的醛類化合物和腈類化合物[12]。因此,該研究不僅擴展了腙參與的親核加成反應的類型,并且三氟甲基的引入往往會賦予母體化合物特殊的化學、物理、生理性質[13],具有重要的理論意義和潛在的應用價值。
甲醛(37%)、三氟乙酸(99%),天津光復精細化工研究所;叔丁基肼鹽酸鹽(97%),上海韶遠化學科技有限公司;氫氧化鈉、碳酸鈉,市售分析純;環(huán)狀N-酰基三氟酮亞胺(Ⅰ)按文獻[14]制備;甲醛 N-叔丁基腙(Ⅱ)按文獻[15]制備;二氯甲烷、四氫呋喃、甲苯、乙腈、甲醇,均經過重蒸處理。
SGW X-4型顯微熔點儀,AVATAR 360FTIR型光譜儀,microTOF-QⅡ型質譜儀,Varian 400MHz型核磁共振儀(內標為Me4Si)。
圖1 甲醛N-叔丁基腙與環(huán)狀N-?;獊啺返挠H核加成反應Fig.1 Nucleophilic addition of formaldehyde N-tertbutyl hydrazone to cyclic N-acyl trifluoromethylketimine
在10mL的Schlenk瓶中加入化合物Ⅰa(19mg,0.05mmol)、Et3N(7.0μL,0.05mmol)、CH2Cl2(2mL),室 溫 攪 拌 下 加 入 化 合 物 Ⅱ (14μL,0.1 mmol),室溫攪拌12h,經TLC檢測反應完全,通過硅膠柱[洗脫劑為:乙酸乙酯∶石油醚(60~90℃)=1∶5(體積比)]純化得到白色固體Ⅲa 15.7mg,熔點47~50℃,收率58%。
在三氟乙酸(TFA)作用下,對加成產物Ⅲa進行進一步的轉化,得到Ⅲa的異構化產物N-叔丁基腙(Ⅳa),如圖2所示。
圖2 加成產物Ⅲa的異構化反應Fig.2 Isomerization of the adductⅢa
在10mL的Schlenk瓶中加入加成產物Ⅲa(105mg,0.3mmol),加入CH2Cl22mL溶解,將體系降至0℃,再滴加TFA(36mg,0.3mmol),攪拌12h后,將飽和NaHCO3溶液加入到反應體系中,然后以乙酸乙酯萃取,無水硫酸鎂干燥,最后柱純化[洗脫劑為:乙酸乙酯∶石油醚(60~90℃)=1∶3(體積比)],得到白色固體Ⅳa 132mg,熔點67~72℃,收率94%。
在環(huán)狀N-?;獊啺酚昧繛?.05mmol、甲醛N-叔丁基腙用量為1.0mmol、堿用量為0.05 mmol、溶劑用量為2mL的條件下,考察堿和溶劑對親核加成反應的影響,結果見表1 。
由表1 可看出,當使用三乙胺(Et3N)和三乙烯二胺(DABCO)時,分離收率不高;當使用堿性更強的1,8-二氮雜二環(huán)[5.4.0]十一碳-7-烯(DBU)時,反應主要生成其它副產物,分離收率很低;當使用強堿弱酸鹽如Na2CO3、K2CO3時,分離收率有較大提高,其中使用Na2CO3時收率最高;當不加堿時,分離收率也能達到83%。參考甲醛腙與三氟甲基酮的加成反應[16],分析認為環(huán)狀N-酰基三氟酮亞胺C=N雙鍵上連有拉電子能力較強的三氟甲基,提高了C=N雙鍵上C原子的親電性,同時醛腙中NH和C=N雙鍵發(fā)生共軛,使得C=N雙鍵中C原子具有親核性[17],因此,即使不加堿時反應仍能進行。
表1 堿和溶劑對親核加成反應的影響Tab.1 Effect of bases and solvents on nucleophilic addition
由表1 還可看出,不同溶劑對分離收率的影響不同。以Na2CO3為堿,當使用甲醇作溶劑時,完全形成了甲氧基與Ⅰa加成的副產物,分離收率為0%;由于底物Ⅰa在乙醚中溶解性較差,因此分離收率較低,為71%;當使用四氫呋喃作溶劑時,反應體系較復雜,副產物的生成降低了分離收率,僅為58%;當使用二氯甲烷、甲苯和二甲苯為溶劑時,分離收率都能達到90%以上(4#、8#和12#)。因此,確定最佳反應條件為:100%Na2CO3作為堿,2mL二氯甲烷作為溶劑,室溫反應12h。
在最優(yōu)反應條件下,對親核加成反應的底物適應性進行研究,反應式如圖3所示,結果見表2 。
圖3 化合物Ⅱ與化合物Ⅰa~Ⅰn的親核加成反應Fig.3 Nucleophilic addition of compoundⅡto compoundsⅠa~Ⅰn
由表2 可以看出,無論環(huán)狀N-酰基三氟酮亞胺中芳環(huán)上的取代基是吸電子基團(Ⅰa~Ⅰd)還是給電子基團(Ⅰf~Ⅰh),都能以中等到好的收率(88%~99%)得到目標產物;即使芳環(huán)上沒有取代基時(Ⅰe)也能以93%的收率獲得加成產物Ⅲe;芳環(huán)上有2個鹵原子取代基(Ⅰi~Ⅰj)時,產物(Ⅲi、Ⅲj)的收率高達95%以上;將底物中N原子上的保護基改為2,4,6-三甲基芐基(Ⅰk)時,能以接近當量的收率(99%)得到目標產物Ⅲk;即使選用位阻較大的1-萘甲基作為保護基(Ⅰl),產物的收率仍能達到97%。由此可見,保護基團的空間位阻作用對該親核加成反應收率的影響并不明顯。但是,當選用溶解性較差的底物Ⅰm時,反應速率減慢,反應時間需延長至2d,同時會伴隨有Ⅰm與水加成的副產物生成,產物的收率有所降低(86%);若將底物中的三氟甲基替換成二氟甲基時,產物的收率明顯下降(Ⅲn)。這是由于,底物Ⅰ中C=N雙鍵鄰位取代基的拉電子能力越強,C=N雙鍵中C原子的親電性就越強,越容易被親核試劑Ⅱ進攻;而Ⅰn中二氟甲基的拉電子能力較弱,因此反應收率降低。
表2 親核加成反應結果Tab.2 Results of nucleophilic addition
Ⅲa:白色固體,收率98%,m.p.47~50 ℃。1HNMR (400MHz,CDCl3),δ:7.25 (s,1H),7.20~7.13(m,3H),6.84(d,J=8.6Hz,2H),6.82~6.75(m,2H),5.11(dd,J=45.3Hz,16.4Hz,2H),4.37~4.27(m,2H),3.76(s,3H),1.15(s,9H)。19FNMR(376MHz,CDCl3),δ:-79.06(s,3F)。13CNMR(100 MHz,CDCl3),δ:159.0,152.5,137.3,130.4,128.3,127.8,127.7,127.2,124.9(q,1JF-C=286.9Hz),117.6,116.4,114.4,70.8,68.9,61.5 (q,2JF-C=28.7 Hz),55.4,45.7,26.7。HRMS(ESI),m/z:found 491.1439[M+Na]+;calcd.for C22H24ClF3N4O2+Na:491.1438。IR (KBr),ν,cm-1:3218,3094,2971,1687,1514,1433,1396,1250,1174,809。
Ⅲb:白色固體,收率88%,m.p.48~51℃。1HNMR(400MHz,CDCl3),δ:7.17(d,J=8.5Hz,2H),7.02(d,J=8.7Hz,1H),6.96~6.91(m,1H),6.87~6.79(m,3H),6.72~6.56(m,1H),5.11(dd,J=39.6 Hz,16.4Hz,2H),4.30(s,2H),3.76(s,3H),1.15(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.94(s,3F),-120.53~ -120.56(m,1F)。13CNMR(100 MHz,CDCl3),δ:159.0,158.0(d,1JF-C=241.1Hz),152.6,134.9,128.5,127.7,125.0(q,1JF-C=286.4Hz),117.5(d,3JF-C=6.6Hz),117.3(d,2JF-C=22.2Hz),116.4 (d,3JF-C=7.6Hz),114.4,114.1 (d,2JF-C=24.7Hz),70.9,69.0,61.5(q,2JF-C=28.9Hz),55.4,45.9,26.7。HRMS(ESI),m/z:found 475.1735 [M+Na]+;calcd.for C22H24F4N4O2+ Na:475.1733。IR(KBr),ν,cm-1:3222,3092,2972,1686,1515,1447,1400,1250,1178。
Ⅲc:白色固體,收率93%,m.p.54~57℃。1HNMR(400MHz,CDCl3),δ:7.37(s,1H),7.31(d,J=8.8 Hz,1H),7.16(d,J=8.4Hz,2H),6.85~6.83(m,3H),6.73(d,J=8.9Hz,1H),5.10(dd,J=44.9Hz,16.4Hz,2H),4.36~4.27(m,2H),3.76(s,3H),1.15(s,9H)。19FNMR(376MHz,CDCl3),δ:-79.06(s,3F)。13CNMR(100MHz,CDCl3),δ:159.0,152.5,137.7,133.3,130.0,128.3,127.7,124.9(q,1JF-C=286.8Hz),118.0,116.7,115.0,114.4,70.8,68.9,61.4(q,2JF-C=28.2Hz),55.4,45.7,26.7。HRMS(ESI),m/z:found 535.0925 [M+Na]+;calcd.for C22H24BrF3N4O2+Na:535.0932。IR(KBr),ν,cm-1:3219,3092,2971,1688,1595,1512,1429,1393,1252,1173,1104,1034,810,523。
Ⅲd:白色固體,收率99%,m.p.48~51℃。1HNMR(400MHz,CDCl3),δ:7.52~7.47(m,2H),7.18(d,J=8.4Hz,2H),7.10~7.02(m,1H),6.96(d,J=8.7 Hz,1H),6.85(d,J=8.5Hz,2H),5.16(dd,J=38.0 Hz,16.4Hz,2H),4.42~4.34(m,2H),3.77(s,3H),1.13(s,9H)。19FNMR(376MHz,CDCl3),δ:-62.17(s,3F),-79.41(s,3F)。13CNMR(100MHz,CDCl3),δ:159.1,152.6,141.5,129.0,128.0,127.7,124.9(q,1JF-C=286.6Hz),124.6,124.6(q,2JF-C=33.2Hz),123.9(q,1JF-C=269.9Hz),116.5,115.3,114.5,70.7,69.0,61.7(q,2JF-C=29.0Hz),55.4,45.8,26.7。HRMS(ESI),m/z:found 525.1694[M+Na]+;calcd.for C23H24F6N4O2+Na:525.1701。IR (KBr),ν,cm-1:3219,3092,2971,1688,1595,1512,1429,1393,1252,1173,1104,1034,810。
Ⅲe:白色固體,收率93%,m.p.43~46℃。1HNMR(400MHz,CDCl3),δ:7.30~7.28(m,1H),7.25~7.17(m,3H),7.02(t,J=7.6Hz,1H),6.87(t,J=9.5Hz,3H),6.60(s,1H),5.15(q,J=16.4Hz,2H),4.36(q,J=13.8Hz,2H),3.77(s,3H),1.18 (s,9H)。19FNMR(376MHz,CDCl3),δ:-78.99(s,3F)。13CNMR(100MHz,CDCl3),δ:158.9,152.7,138.5,130.4,128.8,127.7,126.8,125.2(q,1JF-C=286.8Hz),122.4,116.1,115.0,114.3,71.1,68.8,61.5(q,2JF-C=27.6Hz),55.3,45.6,26.7。HRMS(ESI),m/z:found 457.1827 [M+Na]+;calcd.for C22H25F3N4O2+Na:457.1827。IR (KBr),ν,cm-1:3220,3087,2971,1686,1513,1462,1407,1250,1173,1035,750。
Ⅲf:白色固體,收率89%,m.p.164~166℃。1HNMR(400MHz,CDCl3),δ:7.18(d,J=8.4Hz,2H),7.08~6.99(m,2H),6.83(d,J=8.5Hz,2H),6.75(d,J=8.4Hz,1H),6.54~6.34(m,1H),5.11(dd,J=39.2Hz,16.3Hz,2H),4.33(dd,J=34.7 Hz,13.9Hz,2H),3.75(s,3H),2.25(s,3H),1.17(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.76(s,3F)。13CNMR(100MHz,CDCl3),δ:158.9,152.7,136.1,132.0,131.0,129.0,127.7,127.2,125.2(q,1JF-C=287.2Hz),116.1,115.0,114.3,71.3,68.8,61.4(q,2JF-C=28.2Hz),55.3,45.5,26.7,20.7。HRMS(ESI),m/z:found 471.1976[M + Na]+;calcd.for C23H27F3N4O2+Na:471.1984。IR (KBr),ν,cm-1:3221,3091,2970,1685,1515,1438,1250,1174,1034,810。
Ⅲg:白 色 固 體,收 率 98%,m.p.49~54 ℃。1HNMR(400MHz,CDCl3),δ:7.20(d,J=8.5Hz,2H),7.09(d,J=8.8Hz,2H),6.85~6.79(m,3H),6.45(s,1H),5.20~5.04(m,2H),4.40(d,J=13.9 Hz,1H),4.30(d,J=13.9Hz,1H),3.76(s,3H),1.18(s,15H)。19FNMR(376MHz,CDCl3),δ:-78.78(s,3F)。13CNMR(100MHz,CDCl3),δ:158.9,152.7,143.0,136.2,129.0,128.4,127.8,125.3(q,1JF-C=287.1Hz),124.7,116.0,115.0,114.3,71.3,68.8,61.4(q,2JF-C=28.3Hz),55.3,45.6,33.4,26.8,24.0。HRMS(ESI),m/z:found 499.2286[M +Na]+;calcd.for C25H31F3N4O2+Na:499.2297。IR(KBr),ν,cm-1:3222,3095,2964,1686,1615,1513,1442,1404,1245,1172,1028,901,812,620。
Ⅲh:白色固體,收率89%,m.p.52~55℃。1HNMR(400MHz,CDCl3),δ:7.18(d,J=8.4Hz,2H),6.84~6.82(m,3H),6.78(s,2H),6.38 (s,1H),5.10(dd,J=39.3Hz,16.4Hz,2H),4.32(q,J=13.9 Hz,2H),3.75(s,3H),3.72(s,3H),1.18(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.52 (s,3F)。13CNMR(100MHz,CDCl3),δ:158.9,155.0,152.6,132.1,129.0,127.7,125.2(q,1JF-C=287.1Hz),117.3,116.1,115.6,114.3,112.8,71.3,68.9,61.4(q,2JF-C=28.4Hz),55.7,55.4,45.7,26.7。HRMS(ESI),m/z:found 487.1932 [M+Na]+;calcd.for C23H27F3N4O3+Na:487.1933。IR (KBr),ν,cm-1:3219,3087,2970,1683,1516,1455,1178,1029,810,670,613。
Ⅲi:白色固體,收率96%,m.p.63~66 ℃。1HNMR(400MHz,CDCl3),δ:7.28(t,J=8.4Hz,1H),7.18~7.08(m,3H),6.86(d,J=8.5Hz,2H),6.65(d,J=9.0Hz,1H),5.14(dd,J=35.1Hz,16.4 Hz,2H),4.58(d,J=14.5Hz,1H),4.33~4.29(m,1H),3.79(s,3H),1.16(s,9H)。19FNMR(376MHz,CDCl3),δ:-79.91~-79.95(m,3F),-109.19(s,F)。13CNMR(100MHz,CDCl3),δ:159.1,155.4(d,1JF-C=250.3Hz),152.6,139.0(d,3JF-C=4.9Hz),132.0,128.1,127.7,125.1(q,1JF-C=287.4Hz),115.5 (d,2JF-C=20Hz),114.5,111.4 (d,3JF-C=3.5Hz),106.3(d,2JF-C=16.2Hz),68.8,68.7,61.4(q,2JF-C=30.2Hz),55.4,46.1,26.7。HRMS(ESI),m/z:found 509.1340[M +Na]+;calcd.for C22H23ClF4N4O2+Na:509.1343。IR(KBr),ν,cm-1:3220,3092,2972,1691,1613,1586,1515,1455,1397,1250,1178,1036,801,615。
Ⅲj:白 色 固 體,收 率95%,m.p.48~51 ℃。1HNMR (400MHz,CDCl3),δ:7.15(d,J=8.5Hz,2H),7.06(dd,J=17.8Hz,9.0Hz,1H),6.99(s,1H),6.84(d,J=8.6Hz,2H),6.61~6.58(m,1H),5.11(q,J=16.4Hz,2H),4.57(d,J=14.5Hz,1H),4.33~4.26(m,1H),3.76(s,3H),1.14(s,9H)。19FNMR(376MHz,CDCl3),δ:-79.94(d,J=12.8Hz,3F),-132.80~-132.85(m,1F),-144.42~-144.51(m,1F)。13CNMR(100MHz,CDCl3),δ:159.1,152.7,148.5(dd,1JF-C=250.8Hz,2JF-C=14.7Hz),146.5(dd,1JF-C=243.3Hz,2JF-C= 14.2 Hz),135.7,128.2,127.7,125.1(q,1JF-C= 287.6 Hz),118.6(d,2JF-C= 17.8Hz),114.5,110.4,106.8(d,2JF-C= 12.5Hz),68.9,68.6,61.3(q,2JF-C=29.7 Hz),55.4,46.1,26.7。HRMS(ESI),m/z:found 493.1632[M+Na]+;calcd.for C22H23F5N4O2+Na:493.1639。IR (KBr),ν,cm-1:3222,3094,2972,1690,1612,1514,1477,1400,1250,1176,1036,803,720,643。
Ⅲk:白色固體,收率99%,m.p.190~195℃。1HNMR(400MHz,CDCl3),δ:7.23(s,1H),7.13(d,J=7.1Hz,1H),6.82(s,3H),6.68(d,J=8.9Hz,1H),5.38(d,J=16.3Hz,1H),5.04(d,J=16.3 Hz,1H),4.34~4.28(m,2H),2.31(s,6H),2.24(s,3H),1.14(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.80(s,3F)。13CNMR(100MHz,CDCl3),δ:152.4,137.7,136.8,136.3,130.4,130.4,129.7,129.0,127.7,127.4,124.7(q,1JF-C=286.7Hz),120.4,117.2,115.8,71.4,68.9,61.8(q,2JF-C=28.6Hz),43.2,26.7,20.9,20.2,19.3。HRMS(ESI),m/z:found 503.1800[M+Na]+;calcd.for C24H28ClF3N4O+Na:503.1801。IR(KBr),ν,cm-1:3216,3092,2968,1689,1608,1431,1399,1259,1174,1042,805,697。
Ⅲl:白色固體,收率97%,m.p.194~197 ℃。1HNMR(400MHz,CDCl3),δ:8.06(d,J=8.2Hz,1H),7.92(d,J=7.9Hz,1H),7.77(d,J=8.2Hz,1H),7.63~7.55(m,2H),7.36~7.31(m,2H),7.13~7.08(m,2H),6.84(s,1H),6.58(d,J=8.9Hz,1H),5.69~5.60(m,2H),4.41~4.35(m,2H),1.19(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.91(s,3F)。13CNMR(100MHz,CDCl3),δ:152.4,137.4,134.0,130.6,130.5,130.4,129.2,127.9,127.9,127.2,126.6,126.1,125.7,125.0(q,1JF-C=286.6Hz),122.6,122.4,117.5,116.6,70.9,69.0,61.6(q,2JF-C=28.1Hz),44.3,26.7。HRMS(ESI),m/z:found 511.1484[M+Na]+;calcd.for C25H24ClF3N4O+Na:511.1488。IR(KBr),ν,cm-1:3218,3095,2969,1690,1600,1507,1429,1400,1256,1173,792,560。
Ⅲm:白色固體,收率86%,m.p.162~165℃。1HNMR(400MHz,CDCl3),δ:9.90(s,1H),7.27(s,1H),7.22(d,J=8.2Hz,1H),6.82(d,J=8.3Hz,1H),6.73(s,1H),4.32(s,2H),1.14(s,9H)。19FNMR(376MHz,CDCl3),δ:-78.84(s,3F)。13CNMR(100 MHz,CDCl3),δ:153.6,135.9,130.7,127.9,127.0,124.8(q,1JF-C=286.2Hz),116.6,115.4,71.0,69.0,62.7(q,2JF-C=28.6Hz),26.7。HRMS(ESI),m/z:found 347.0887 [M-H]+;calcd.for C14H16ClF3N4O -H:347.0886。IR (KBr),ν,cm-1:3318,3210,3124,3067,2978,1700,1502,1434,1254,1195,1173,865,827,739。
Ⅲn:白色固體,收率80%,m.p.47~51℃。1HNMR(400MHz,CDCl3),δ:7.21(s,1H),7.17~7.13(m,3H),6.84(d,J=8.5Hz,2H),6.75(d,J=8.9Hz,1H),6.30~6.23(m,1H),5.92(t,J=55.6Hz,1H),5.16(d,J=16.4Hz,1H),4.99(d,J=16.4Hz,1H),4.26 (d,J=13.8Hz,1H),4.14 (d,J=13.8 Hz,1H),3.76(s,3H),1.17(s,9H)。19FNMR(376 MHz,CDCl3),δ:-128.95(dd,J=278.24Hz,1F),-131.40(dd,J=278.62Hz,1F)。13CNMR(100 MHz,CDCl3),δ:159.0,153.0,137.2,129.9,128.5,127.7,127.7,126.6,119.0,116.2,115.5(t,1JF-C=250.8Hz),114.4,71.8,69.0,60.7(t,2JF-C=21.2 Hz),55.4,45.7,26.8。HRMS(ESI),m/z:found 473.1526 [M+Na]+;calcd.for C22H25ClF2N4O2+Na:473.1532。IR (KBr),ν,cm-1:3224,3096,2970,1685,1604,1513,1396,1249,1176,1083,809,549。
Ⅳa:白色固體,收率 94%,m.p.67~72℃。1HNMR(400MHz,CDCl3),δ:7.30(s,1H),7.23~7.11(m,4H),6.84(d,J=8.6Hz,2H),6.78(d,J=8.9Hz,1H),6.33(s,1H),5.18(d,J=16.4Hz,1H),5.00(d,J=16.5Hz,1H),3.76(s,3H),1.21(s,9H)。19FNMR(376MHz,CDCl3),δ:-79.31(s,3F)。13CNMR(100MHz,CDCl3),δ:159.0,152.3,137.1,130.3,129.1,128.4,127.8,127.7,127.2,124.5(q,1JC-F=286.8Hz),118.1,116.5,114.4,61.7(q,2JC-F=28.6Hz),55.4,54.5,45.7,28.5。HRMS(ESI),m/z:found 491.1426 [M +Na]+;calcd.for C22H24ClF3N4O2+Na:491.1438。IR(KBr),ν,cm-1:3416,3222,3096,2970,1684,1510,1427,1247,1180,1031,812。
在堿的促進下,通過甲醛N-叔丁基腙與環(huán)狀N-?;獊啺返挠H核加成反應,首次合成了新型三氟甲基取代偶氮化合物。以Na2CO3為堿、以二氯甲烷為溶劑,在室溫下,得到了收率80%~99%的系列加成產物;進一步研究表明該加成產物在酸性條件下容易發(fā)生異構化反應形成腙,它是一類非常重要的中間體,易轉化為醛和腈類化合物。
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