Citation: He Zhenxiu, Zhou Yongyun, Sun Weiqing, Fan Ruifeng, Shen Guol, Fan Baomin. Asymmetric Ring Opening Reaction of Oxabenzonorbornadienes with Phenols Promoted by Rhodium/Zinc Complexes[J]. Chinese Journal of Organic Chemistry, 2019, 39(3): 754-760. doi: 10.6023/cjoc201808027
铑/锌共催化苯酚对氧杂苯并降冰片烯的不对称开环反应研究
English
Asymmetric Ring Opening Reaction of Oxabenzonorbornadienes with Phenols Promoted by Rhodium/Zinc Complexes
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Key words:
- rhodium
- / oxabenzonorbornadienes
- / Co-catalysis
- / symmetric ring opening reaction
- / Lewis acid
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氢化萘结构单元广泛存在于具有生物活性的天然产物及药物分子当中[1], 相应的合成研究也因此受到广泛关注[2].过渡金属催化的杂原子亲核试剂对氧/氮杂苯并降冰片烯的开环反应是近年来发展起来的构筑氢化萘结构单元的重要方法之一[3].而发展简单、有效的手性催化体系对此类反应显得尤为重要.自Lautens课题组[4]首次开展这方面研究工作以来, 氧/氮杂苯并降冰片烯的不对称开环反应已经取得很大进展.各种手性的过渡金属催化体系被发展, 用于催化碳亲核试剂、杂原子亲核试剂对氧/氮杂苯并降冰片烯的不对称开环反应, 构筑具有多功能团的手性氢化萘结构中间体.如铑催化的酚[4]、醇[5]、胺[6]、硫醇[7]、酸[8]、水[9]或其它一些杂原子亲核试剂[10]对氧/氮杂苯并降冰片烯的不对称开环反应.此外, 杨定乔[11]、汤文军课题组[12]也发展了一些铱催化的杂原子亲核试剂对氧/氮杂苯并降冰片烯的不对称开环反应.
最近, 我们课题组对过渡金属催化的杂原子亲核试剂与氧/氮杂苯并降冰片烯的不对称开环反应非常感兴趣, 并取得很好的研究进展[13].尤其是Rh/BDPP [(R, R)-BDPP=(2R, 4R)-(+)-2, 4-bis(diphenylphosphino)pentane]手性剂催化条件下, 分别实现了胺[13g]、羧酸[13i]对氧杂苯并降冰片烯的不对称开环反应, 并取得良好的收率和较高的对映选择性.为拓展此手性催化剂对其它杂原子亲核试剂的适用性, 我们尝试将此催化条件应用于酚对氧杂苯并降冰片烯的不对称开环反应, 并取得了较好的收率和对映选择性.
1. 结果与讨论
1.1 反应条件的优化
在前期研究的基础上, 采用7-氧杂苯并降冰片烯(1a) (0.3 mmol)和苯酚(2a) (0.9 mmol)作为标准底物, 我们对二者间的不对称开环反应进行了系统的研究.采用[Rh(COD)Cl]2为催化剂前体、(R, R)-BDPP为配体、1, 2-二氯乙烷(DCE)为溶剂及40 ℃的加热条件下, 7-氧杂苯并降冰片烯(1a)与苯酚(2a)只生成了微量的目标产物3aa(表 1, Entry 1).筛选了其他几种溶剂, 除了1, 2-二甲氧基乙烷(DME)和N, N-二甲基甲酰胺(DMF)只能生成少量的开环产物外(Entries 2, 3), 1, 4-二氧六环和四氢呋喃(THF)都能得到很好收率和不错的对映选择性(Entries 5, 6), 甲苯虽收率高但ee值偏低.综合分析四氢呋喃在此不对称开环反应中比较适合.在温度实验中, 降低温度不能有效改善对应选择性, 反而降低了收率; 升高温度能提高反应速率, 但ee值也随之降低(Entries 7~9).
表 1

Entry Solvent Time/h Yieldb/% ee c/% 1 DCE 6 Trace — 2 DME 21 37 82 3 DMF 21 Trace — 4 Toluene 12 93 75 5 1, 4-Dioxane 1 87 84 6 THF 0.5 94 82 7d THF 28 10 83 8e THF 4 84 83 9f THF 0.3 98 77 a Reaction conditions: 1a (0.30 mmol), 2a (0.90 mmol), ZnI2 (0.03mmol), solvent (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP (6.5 mol%). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 0 ℃. e React at room temperature. f React at 60℃. 为提高其开环产物的对映选择性, 筛选了一些手性配体(图 1).当使用手性配体(R, R)-Me-DUPHOS和单膦配体(R)-Monophos时只生成微量的目标开环产物3aa(表 2, Entries 1, 2).采用(R)-Difuorphos时7-氧杂苯并降冰片烯(1a)异构化成萘酚(Entry 3), (R)-BINAPh和(R, R)-Chi- raphos也只得到少量2a的开环产物(Entry 4, 8).当使用(R, R)-DIOP时, 可得到高收率的开环产物, 但对映选择性降低; 使用配体(R, R)-BDPP时, 收率为94%, 对映选择性为82% (Entry 7).
图 1
表 2

Entry Ligand Time/h Yieldb/% eec/% 1 (R, R)-Me-DUPHOS 10 Trace — 2 (R)-Monophos 8 Trace — 3 R-DIFLUORPHOS 5 Naphthol — 4 (R)-BINAP 10 Trace — 5 R-SEGPHOS 14 83 10 6 (R, R)-DIOP 1 95 56 7 (R, R)-BDPP 0.5 94 82 8 (R, R)-Chiraphos 10 Trace — a Reaction conditions: 1a (0.30 mmol), 2a (0.9 mmol), ZnI2 (0.03mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%) and a bidentate ligand (6.5 mol%) or monodentate ligand (11.0 mol%).b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. 同时也对不同的添加剂进行了筛选, 结果见表 3.结果表明, 添加剂的筛选有助于提高产物的对映选择性.不添加路易斯酸时, 有95%的收率和66%的ee值(Entry 9), 加入三氟甲磺酸盐如CuOTf, AgOTf, Zn(OTf)2和AgBF4时只能得到极少量的开环产物(Entries 3~6).可能是三氟甲磺酸根负离子和四氟硼酸负离子和[Rh(COD)Cl]2中的氯离子发生交换, 抑制了其催化活性.当把路易斯酸换成CuI, CuBr, ZnI2时, 开环产物的对映选择性提高到80%以上(Entries 1, 2, 7), (n-Bu)4NI同样可以作为路易斯酸, 获得77%的对映选择性, 分析是亚铜离子、锌离子或四丁基胺离子和1a上氧络合, 活化了其反应活性, 其中ZnI2效果最好.综合权衡, 选择ZnI2为添加剂.
表 3

Entry Additive Time/h Yieldb/% eec/% 1 CuI 1.4 67 81 2 CuBr 2.3 98 80 3 CuOTf 26 Trace — 4 AgBF4 13 Trace — 5 AgOTf 13 Trace — 6 Zn(OTf)2 13 Trace — 7 ZnI2 0.5 94 82 8 (n-Bu)4NI 2 96 77 9 — 1 95 66 a Reaction conditions: 1a (0.30 mmol), 2a (0.9 mmol), additives (0.03mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP (6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. 1.2 适用底物范围研究
在最佳反应条件下, 对催化苯酚与氧杂苯并降冰片烯不对称开环反应的底物适用范围进行了研究.首先对具有不同取代基的苯酚进行考察, 结果见表 4, 可以看出, 具有吸电子基团的苯酚(Entries 2~5), 除了吸电子能力很强的4-氟苯酚需要通过升温来提高反应活性外, 其余的都能够以很好的收率和较高的对映选择性得到相对应的开环产物.具有供电子基团的苯酚(Entries 6, 9)与带有吸电子基团的苯酚相比, 其收率和ee值略有降低, 但影响不大, 说明该催化体系对不同电子效应的苯酚类底物有良好的耐受性.我们对空间位阻效应也进行了考察(Entries 6~8, 10), 可以看出, 不同位置有取代基时都能得到较好的结果, 换成大位阻取代基(Entry 10)时, 也得到了72%的产率和76%的ee值.
表 4

Entry Phenol Time/h Yieldb/% eec/% 1 
0.5 94 82 2 d 
39 80 69 3 
1.5 92 82 4 
3.5 92 74 5 
2 96 81 6 
3 89 78 7 
12 84 78 8 
6 54 78 9 
0.5 72 76 10 
3 78 82 a Reaction conditions: 1a (0.30 mmol), 2a~2j (0.9 mmol), additives (0.03 mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP(6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 60 ℃. 随后, 我们以结果最好而又最简单的苯酚1a为亲核试剂, 对一系列不同取代基的氧杂苯并降冰片烯进行了研究, 结果见表 5.可以看出, 不同电性和不同位阻的氧杂苯并降冰片烯均能与苯酚进行不对称开环反应, 达到84%~95%的产率和不错的对映选择性, 除了1d得到中等产率62%的开环产物(Entry 3).
表 5

Entry Oxabenzonorbornadiene Time/h Yieldb/% eec/% 1 
2 84 75 2 
31 90 80 3 
48 62 78 4 
29 88 85 5 d 
27 95 78 6 
2 85 80 a Reaction conditions: 1b~1g (0.30 mmol), 2a (0.9 mmol), additives (0.03 mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP(6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 60 ℃. 2. 结论
我们发展了[Rh(COD)Cl]2/ZnI2/(R, R)-BDPP作为共催化体系, 能有效地催化酚类亲核试剂对氧杂苯并降冰片烯的不对称亲核开环反应, 获得较好的收率和良好的ee值.一系列不同取代的氧杂苯并降冰片烯及酚类亲核试剂底物应用于此反应体系中, 表明在温和的条件下, 能够高效而又经济地合成不同取代的含手性四氢萘结构单元的化合物.
3. 实验部分
3.1 仪器与试剂
1H NMR和13C NMR用Brucker 400 MHz核磁共振仪测定(CDCl3为溶剂, TMS为内标); HPLC用Agilent 1260高效液相色谱仪测定, 使用AD-H, AS-H, OD-H, OJ-H手性柱, 洗脱剂为异丙醇和正己烷.反应所用的金属、配体、反应原料及添加剂均在Mikrouna, Supper 1220/750手套箱中称量并操作, 无水溶剂THF、甲苯、二氧六环经钠-二苯甲酮处理, 重蒸后氩气氛围保存并使用; 无水DCE、DMF经氢化钙处理, 重蒸后氩气氛围保存并使用.所用到的铑金属前体和手性配体均从Stream、Aldrich或Acros公司购买.
3.2 实验方法
3.2.1 苯酚对氧杂苯并降冰片烯不对称开环反应
于氩气氛围的手套箱内准确称取[Rh(COD)Cl]2 (1.8 mg, 0.0037 mmol), (R, R)-BDPP (4.3 mg, 0.0097 mmol)于反应管中, 加入1.0 mL THF, 室温下搅拌30 min, 然后加入ZnI2 (9.6 mg, 0.03 mmol)搅拌10 min, 加入氧杂苯并降冰片烯1a (43.2 mg, 0.3 mmol)搅拌10 min后加入苯酚2a (86.7 mg, 0.9 mmol)和1.0 mL THF, 封口后取出手套箱, 于40 ℃油浴下搅拌, 直至底物1a反应完全(TLC检测).反应液浓缩后经中性氧化铝柱层析纯化, 得到产物3aa (67.2 mg, 94% yield), ee值(82%)由HPLC测定.
(1S, 2S)-2-苯氧基-1, 2-二氢萘酚(3aa)[4b]:白色固体, 产率94%, 82% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i- PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=7.54 min, tmajor=10.11 min. m.p. 109~110 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.64 (d, J=6.9 Hz, 1H), 7.35~7.21 (m, 4H), 7.16~7.08 (m, 1H), 7.03~6.92 (m, 3H), 6.51 (d, J=9.8 Hz, 1H), 6.02 (d, J=9.8 Hz, 1H), 5.23~5.07 (m, 2H), 2.68 (d, J=3.4 Hz, 1H).
(1S, 2S)-(4-氟苯氧基)-1, 2-二氢萘酚(3ab)[4b]:白色固体, 产率80%, 69% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=8.48 min, tmajor=10.10 min. m.p. 127~129 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.56 (d, J=6.8 Hz, 1H), 7.26~7.16 (m, 3H), 7.05 (d, J=6.9 Hz, 1H), 6.92 (t, J=8.4 Hz, 2H), 6.84 (dd, J=9.2, 4.4 Hz, 2H), 6.45 (d, J=9.9 Hz, 1H), 5.92 (d, J=9.9 Hz, 1H), 5.09 (d, J=10.1 Hz, 1H), 4.95 (d, J=10.1 Hz, 1H), 2.53 (s, 1H).
(1S, 2S)-2-(4-氯苯氧基)-1, 2-二氢萘酚(3ac)[4b]:白色固体, 产率92%, 82% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=9.61 min, tmajor=12.46 min. m.p. 125~125.5 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.54 (d, J=6.7 Hz, 1H), 7.27~7.13 (m, 4H), 7.04 (d, J=6.7 Hz, 1H), 6.80 (d, J=8.4 Hz, 2H), 6.44 (d, J=9.9 Hz, 1H), 5.89 (d, J=9.9 Hz, 1H), 5.08 (d, J=10.1 Hz, 1H), 4.97 (d, J=10.1 Hz, 1H), 2.57 (d, J=3.8 Hz, 1H).
(1S, 2S)-2-(4-溴苯氧基)-1, 2-二氢萘酚(3ad)[4b]:白色固体, 产率92%, 74% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=10.06 min, tmajor=13.86 min. m.p. 145~146 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.62 (d, J=6.7 Hz, 1H), 7.38 (d, J=8.4 Hz, 2H), 7.34~7.25 (m, 2H), 7.12 (d, J=6.6 Hz, 1H), 6.83 (d, J=8.4 Hz, 2H), 6.52 (d, J=9.9 Hz, 1H), 5.96 (d, J=9.8 Hz, 1H), 5.16 (d, J=10.1 Hz, 1H), 5.05 (d, J=10.1 Hz, 1H), 2.63 (s, 1H).
(1S, 2S)-2-(4-碘苯氧基)-1, 2-二氢萘酚(3ae)[4b]:白色固体, 产率96%, 81% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=10.84 min, tmajor=15.64 min. m.p. 160~162 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.60 (dd, J=19.8, 7.7 Hz, 3H), 7.30 (q, J=6.2, 5.3 Hz, 2H), 7.13 (d, J=6.2 Hz, 1H), 6.74 (d, J=8.4 Hz, 2H), 6.53 (d, J=9.8 Hz, 1H), 5.97 (d, J=9.8 Hz, 1H), 5.17 (d, J=9.4 Hz, 1H), 5.06 (d, J=9.9 Hz, 1H), 2.56 (d, J=3.9 Hz, 1H).
(1S, 2S)-2-(4-甲基苯氧基)-1, 2-二氢萘酚(3af)[4b]:白色固体, 产率89%, 78% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=9.12 min, tmajor=13.29 min. m.p. 80~81 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.62 (d, J=6.7 Hz, 1H), 7.31~7.18 (m, 2H), 7.08 (t, J=6.7 Hz, 3H), 6.87~6.80 (m, 2H), 6.47 (d, J=9.9 Hz, 1H), 5.99 (d, J=9.9 Hz, 1H), 5.15 (d, J=10.3 Hz, 1H), 5.04 (d, J=10.3 Hz, 1H), 2.78 (s, 1H), 2.28 (s, 3H).
(1S, 2S)-2-(2-甲基苯氧基)-1, 2-二氢萘酚(3ag): 白色固体, 产率84%, 78% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=32.5 min, tmajor=34.64 min. m.p. 101~102 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.57 (d, J=6.9 Hz, 1H), 7.27~7.15 (m, 2H), 7.14~7.01 (m, 3H), 6.87~6.75 (m, 2H), 6.43 (d, J=9.9 Hz, 1H), 5.94 (d, J=9.9 Hz, 1H), 5.15 (d, J=10.4 Hz, 1H), 5.04 (d, J=10.3 Hz, 1H), 2.52 (s, 1H), 2.19 (s, 2H).
(1S, 2S)-2-(2, 5-二甲基苯氧基)-1, 2-二氢萘酚(3ah):白色固体, 产率54%, 78% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i-PrOH)=70/30, 1.0 mL/min, 254 nm; tminor=6.39 min, tmajor=5.09 min. m.p. 78~80 ℃. 1H NMR (CDCl3, 400 MHz) δ: 7.65 (d, J=6.9 Hz, 1H), 7.28 (dd, J=13.6, 7.6 Hz, 2H), 7.09 (dd, J=25.3, 7.2 Hz, 2H), 6.76~6.66 (m, 2H), 6.50 (d, J=9.9 Hz, 1H), 6.02 (d, J=9.9 Hz, 1H), 5.22 (d, J=10.4 Hz, 1H), 5.11 (d, J=10.6 Hz, 1H), 2.58 (d, J=3.5 Hz, 1H), 2.29 (s, 3H), 2.22 (s, 3H); 13C NMR (CDCl3, 100 MHz) δ: 155.30, 136.76, 135.62, 131.98, 130.92, 128.76, 128.16, 127.97, 126.72, 126.40, 125.11, 124.60, 121.81, 113.91, 79.40, 72.62, 21.44, 16.17; HRMS (ESI) calcd for C18H18O2: 266.1313; found 266.1307.
(1S, 2S)-2-(4-甲氧基苯氧基)-1, 2-二氢萘酚(3ai)[4b]:白色固体, 产率72%, 76% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n- hexane)/V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=13.51 min, tmajor=19.55 min. m.p. 91~92 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.62 (d, J=6.8 Hz, 1H), 7.32~7.20 (m, 2H), 7.09 (d, J=6.7 Hz, 1H), 6.92~6.78 (m, 4H), 6.47 (d, J=9.9 Hz, 1H), 5.99 (d, J=9.9 Hz, 1H), 5.14 (d, J=9.9 Hz, 1H), 4.98 (d, J=10.2 Hz, 1H), 3.75 (s, 3H).
(1S, 2S)-2-(萘氧基-1, 2-二氢萘酚(3aj): 白色固体, 产率78%, 82% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i- PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=7.73 min, tmajor=11.32 min. m.p. 139~141 ℃; 1H NMR (CDCl3, 400 MHz) δ: 8.21 (d, J=7.5 Hz, 1H), 7.73 (d, J=7.6 Hz, 1H), 7.59 (d, J=6.9 Hz, 1H), 7.47~7.35 (m, 3H), 7.32~7.13 (m, 3H), 7.06 (d, J=6.5 Hz, 1H), 6.79 (d, J=7.6 Hz, 1H), 6.45 (d, J=9.9 Hz, 1H), 6.01 (d, J=9.9 Hz, 1H), 5.27 (q, J=10.4 Hz, 2H); 13C NMR (CDCl3, 100 MHz) δ: 152.98, 135.53, 134.82, 131.94, 129.12, 128.25, 128.08, 127.66, 126.57, 126.52, 126.24, 126.03, 125.79, 125.45, 125.30, 121.96, 121.10, 106.74, 79.65, 72.55; HRMS (ESI) calcd for C20H16O2: 288.1141, found 288.1150.
(1S, 2S)-6, 7-二甲基-2-苯氧基-1, 2-二氢萘酚(3ba):白色固体, 产率84%, 75% ee. HPLC: Daicel Chiralcel OJ-H column (25 cm×0.46 cm ID), conditions: V(n- hexane)/V(i-PrOH)=80/20, 1.0 mL/min, 254 nm, tminor=11.86 min, tmajor=10.63 min. m.p. 181~183 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.33 (s, 1H), 7.28~7.16 (m, 2H), 6.97~6.83 (m, 4H), 6.41 (d, J=9.8 Hz, 1H), 5.90 (d, J=9.8 Hz, 1H), 5.09~4.98 (m, 2H), 2.53 (s, 1H), 2.21 (d, J=14.3 Hz, 6H); 13C NMR (CDCl3, 100 MHz) δ: 156.41, 135.67, 135.11, 131.76, 128.64, 128.46, 127.95, 126.96, 125.76, 123.81, 120.31, 114.79, 77.96, 71.15, 18.69, 18.35. HRMS (ESI) calcd for C18H18O2: 266.1311, found 266.1307.
(1S, 2S)-5, 8-二甲基-2-苯氧基-1, 2-二氢萘酚(3ca): 无色油, 90%, 80% ee. HPLC: Daicel Chiralcel OJ-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i- PrOH)=60/40, 1.0 mL/min, 254 nm; tminor=14.22 min, tmajor=22.20 min. 1H NMR (CDCl3, 400 MHz) δ: 7.29 (t, J=7.4 Hz, 2H), 7.12 (d, J=9.9 Hz, 1H), 7.06~6.92 (m, 3H), 6.79 (s, 2H), 6.13 (dd, J=10.1, 4.8 Hz, 1H), 5.30 (s, 1H), 5.06 (s, 1H), 3.79 (s, 6H); 13C NMR (CDCl3, 100 MHz) δ: 157.51, 151.57, 150.04, 129.59, 124.20, 123.51, 122.86, 121.14, 121.07, 115.88, 111.59, 111.16, 73.81, 65.00, 56.21, 55.92.
(1S, 2S)-6, 7-二甲氧基-2-苯氧基-1, 2-二氢萘酚(3da):白色固体, 产率62%, 78% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i-PrOH)=70/30, 1.0 mL/min, 254 nm, tminor=8.30 min, tmajor=20.18 min. m.p. 58~59 ℃; 1H NMR (CDCl3, 400 MHz) δ: 7.22 (t, J=7.8 Hz, 2H), 7.12 (s, 1H), 6.89 (t, J=7.0 Hz, 3H), 6.59 (s, 1H), 6.35 (d, J=9.8 Hz, 1H), 5.86 (d, J=9.8 Hz, 1H), 5.02 (q, J=10.3 Hz, 2H), 3.85 (s, 3H), 3.80 (s, 3H); 13C NMR (CDCl3, 100 MHz) δ: 156.35, 147.75, 147.35, 128.65, 127.60, 127.34, 123.66, 123.07, 120.35, 114.79, 109.12, 108.09, 78.04, 71.24, 55.02.
(6S, 7S)-6, 7-二噁烷-2-苯氧基-1, 2-二氢萘酚(3ea):无色油, 88%, 85% ee. HPLC: Daicel Chiralcel OJ-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i- PrOH)=80/20, 1.0 mL/min, 254 nm, tminor=29.31 min, tmajor=44.09 min. m.p. 242~244 ℃. 1H NMR (CDCl3, 400 MHz) δ: 7.27~7.16 (m, 2H), 7.07 (s, 1H), 6.95~6.85 (m, 3H), 6.59 (s, 1H), 6.33 (d, J=9.8 Hz, 1H), 5.85 (d, J=9.6 Hz, 1H), 4.97 (s, 2H), 4.19 (s, 4H), 2.43 (s, 1H); 13C NMR (CDCl3, 100 MHz) δ: 157.44, 143.34, 129.68, 128.44, 125.65, 124.31, 121.38, 115.84, 115.64, 115.27, 115.18, 78.81, 71.93, 64.49, 64.42.
(5S, 6S)-6, 7-亚甲二氧基-2-苯氧基-1, 2-二氢萘酚(3fa):白色固体, 产率95%, 78% ee. HPLC: Daicel Chiralcel OJ-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/V(i-PrOH)=80/20, 1.0 mL/min, 254 nm; tminor=20.56 min, tmajor=33.54 min. m.p. 110~112 ℃; 1H NMR (DMSO-d6, 400 MHz) δ: 7.32 (t, J=7.8 Hz, 2H), 7.09 (s, 1H), 6.99 (dd, J=20.3, 7.8 Hz, 3H), 6.85 (s, 1H), 6.51 (d, J=9.8 Hz, 1H), 6.04 (d, J=7.1 Hz, 2H), 5.93 (d, J=9.8 Hz, 1H), 5.02 (d, J=8.4 Hz, 2H), 4.82 (t, J=7.1 Hz, 1H), 3.41 (s, 1H); 13C NMR (DMSO-d6, 100 MHz) δ: 157.51, 146.67, 146.48, 131.65, 129.55, 128.59, 125.88, 124.29, 120.71, 115.62, 107.41, 107.03, 100.94, 77.52, 70.28, 70.18. HRMS (ESI) calcd for C17H14O4: 282.0890, found 282.0892.
(1S, 2S)-6, 7-二溴-2-苯氧基-1, 2-二氢萘酚(3ga): 无色油, 85%, 80% ee. HPLC: Daicel Chiralcel AD-H column (25 cm×0.46 cm ID), conditions: V(n-hexane)/ V(i-PrOH)=90/10, 1.0 mL/min, 254 nm; tminor=11.21 min, tmajor=24.50 min. 1H NMR (DMSO-d6, 400 MHz) δ: 7.72 (s, 1H), 7.57 (s, 1H), 7.23 (t, J=7.7 Hz, 2H), 6.96~6.85 (m, 3H), 6.52 (d, J=9.8 Hz, 1H), 6.08~5.94 (m, 2H), 5.02 (d, J=9.2 Hz, 1H), 4.86~4.76 (m, 1H); 13C NMR (DMSO-d6, 100 MHz) δ: 156.37, 137.78, 132.26, 130.28, 129.96, 128.61, 128.05, 125.69, 124.45, 121.87, 121.47, 119.97, 114.69, 80.11, 76.09, 68.61. HRMS (ESI) calcd for C16H12O2Br2: 393.9215, found 393.9204.
辅助材料(Supporting Information) 不对称开环产物核磁谱图和高效液相谱图.这些材料可以免费从本刊网站(http://sioc-journal.cn/)上下载.
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[1]
(a) Jeffs, P. W.; Lynn, D. G. J. Org. Chem. 1975, 40, 2958.
(b) Okuno, T.; Natsume, I.; Sawai, K.; Sawamura, K.; Furusaki, A.; Matsumoto, T. Tetrahedron Lett. 1983, 24, 5653.
(c) Snyder, S. E.; Aviles-Garay, F. A.; Chakraborti, R.; Nichols, D. E.; Watts, V. J.; Mailman, R. B. J. Med. Chem. 1995, 38, 2395.
(d) Hsieh, T. J.; Chang, F. R.; Chia, Y. C.; Chen, C. Y.; Lin, H. C.; Chiu, H. F.; Wu, Y. C. J. Nat. Prod. 2001, 64, 1157.
(e) Idris, A.; Tantry, M. A.; Ganai, B. A.; Kamili, A. N.; Williamson, J. S. Phytochem. Lett. 2015, 11, 264. -
[2]
(a) Lautens, M.; Fagnou, K.; Hiebert, S. Acc. Chem. Res. 2003, 36, 48.
(b) Rayabarapu, D. K.; Cheng, C. H. Acc. Chem. Res. 2007, 40, 971. -
[3]
(a) Yang, D.-Q.; Han, Y.-F. Chin. J. Org. Chem. 2006, 26, 1613(in Chinese).
(杨定乔, 韩英锋, 有机化学, 2006, 26, 1613.)
(b) Cho, Y. H.; Tseng, N. W.; Senboku, H.; Lautens, M. Synthesis 2008, 2467.
(c) Dockendorff, C.; Jin, S. J.; Olsen, M.; Lautens, M.; Coupal, M.; Hodzic, L.; Spear, N.; Payza, K.; Walpole, C.; Tomaszewski, M. J. Bioorg. Med. Chem. Lett. 2009, 19, 1228.
(d) Liébert, C.; Brinks, M. K.; Capacci, A. G.; Fleming, M. J.; Lautens, M. Org. Lett. 2011, 13, 3000. -
[4]
(a) Lautens, M.; Fang, Y. Q. Org. Lett. 2003, 5, 3679.
(b) Lautens, M.; Fagnou, K.; Taylor, M. Org. Lett. 2000, 2, 1677. -
[5]
(a) Fagnou, M. K.; Taylor, M.; Rovis, T. J. Organomet. Chem. 2001, 624, 259.
(b) Tsui, G. C.; Dougan, P.; Lautens, M. Org. Lett. 2013, 15, 2652. -
[6]
(a) Lautens, M.; Fagnou, K.; Rovis, T. J. Am. Chem. Soc. 2000, 122, 5650.
(b) Lautens, M.; Fagnou, K. J. Am. Chem. Soc. 2001, 123, 7170.
(c) Lautens, M.; Fagnou, K.; Yang, D. Q. J. Am. Chem. Soc. 2003, 125, 14884.
(d) Cho, Y. H.; Zunic, V.; Senboku, H.; Olsen, M.; Lautens, M. J. Am. Chem. Soc. 2006, 128, 6837. -
[7]
Leong, P.; Lautens, M. J. Org. Chem. 2004, 69, 2194. doi: 10.1021/jo035730e
-
[8]
Lautens, M.; Fagnou, K. Tetrahedron 2001, 57, 5067. doi: 10.1016/S0040-4020(01)00351-9
-
[9]
Tsui, G. C.; Lautens, M. Angew. Chem. Int. Ed. 2012, 51, 1. doi: 10.1002/anie.201106864
-
[10]
(a) Tsui, G. C.; Tsoung, J.; Dougan, P.; Lautens, M. Org. Lett. 2012, 14, 5542.
(b) Murakami, M.; Igawa, H. Chem. Commun. 2002, 4, 390.
(c) Preetz, A.; Kohrt, C.; Drexler, H.; Torrens, A.; Buschmann, H.; Lopez, M.; Heller, D. Adv. Synth. Catal. 2010, 352, 2073. -
[11]
(a) Yang, D.-Q.; Long, Y.-H.; Wang, H.; Zhang, Z.-M. Org. Lett. 2008, 10, 4723.
(b) Yang, D.-Q.; Long, Y.-H.; Zhang, J.-F.; Zeng, H.-P.; Wang, S.-Y.; Li, C.-R. Organometallics 2010, 29, 3477.
(c) Cheng, H.-C.; Yang, D.-Q. J. Org. Chem. 2012, 77, 9756.
(d) Long, Y.-H.; Wang, W.-L.; Yang, D.-Q.; Jiang, H.; Chen, K.-X.; Fang, Y.-L. Mol. Diversity 2014, 18, 101. -
[12]
Luo, R.-S.; Liao, J.-H.; Xie, L.; Tang, W.-J.; Chan, A. S. C. Chem. Commun. 2013, 49, 9959. doi: 10.1039/c3cc46009f
-
[13]
(a) Li, S.-F.; Chen, H.-L.; Yang, Q.-J.; Yu, L.; Fan, C.-L.; Zhou, Y.-Y.; Wang, J.; Fan, B.-M. Asian J. Org. Chem. 2013, 2, 494.
(b) Yu, L.; Zhou, Y.-Y.; Xu, X.; Li, S.-F.; Xu, J.-B.; Fan, B.-M.; Lin, C.-Y.; Bian, Z.-X.; Chan, A. S. C. Tetrahedron Lett. 2014, 55, 6315.
(c) Lu, Z.-W.; Wang, J., Han, B.-Q.; Li, S.-F.; Zhou, Y.-Y.; Fan, B.-M. Adv. Synth. Catal. 2015, 357, 3121.
(d) Zeng, C. Y.; Yang, F.; Chen, J. C.; Wang, J.; Fan, B. M. Org. Biomol. Chem. 2015, 13, 8425.
(e) Zhou, Y.-Y.; Lu, Z.-W.; Han, B.-Q.; Zeng, C. Y.; Zhang, Z.-H.; Fan, B.-M. Tetrahedron: Asymmetry 2015, 26, 1354.
(f) Li, S.-F.; Xu, J.-B.; Fan, B.-M.; Lu, Z.-W.; Zeng, C.-Y.; Bian, Z.-X.; Zhou, Y.-Y.; Wang, J. Chem.-Eur. J. 2015, 21, 9003.
(g) Xu, X.; Chen, J.-C.; He, Z.-X.; Zhou, Y.-Y.; Fan, B.-M. Org. Biomol. Chem. 2016, 14, 2480.
(h) Zhou, Y.-Y.; Gu, C.-P.; Chen, J.-C.; Zhu, M.-N.; Yang, F.; Jianbin Xu, J.-B.; Fan, B.-M. Adv. Synth. Catal. 2016, 358, 3167.
(i) He, X.-B.; Chen, J.-C.; Xu, X.; Yang, F.; Gu, C.-P.; Zhou, Y.-Y.; Fan, B.-M. Tetrahedron: Asymmetry 2017, 28, 62.
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表 1 溶剂和温度的筛选a
Table 1. Optimization of solvent and temperature

Entry Solvent Time/h Yieldb/% ee c/% 1 DCE 6 Trace — 2 DME 21 37 82 3 DMF 21 Trace — 4 Toluene 12 93 75 5 1, 4-Dioxane 1 87 84 6 THF 0.5 94 82 7d THF 28 10 83 8e THF 4 84 83 9f THF 0.3 98 77 a Reaction conditions: 1a (0.30 mmol), 2a (0.90 mmol), ZnI2 (0.03mmol), solvent (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP (6.5 mol%). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 0 ℃. e React at room temperature. f React at 60℃. 表 2 配体筛选a
Table 2. Screening of chiral ligands

Entry Ligand Time/h Yieldb/% eec/% 1 (R, R)-Me-DUPHOS 10 Trace — 2 (R)-Monophos 8 Trace — 3 R-DIFLUORPHOS 5 Naphthol — 4 (R)-BINAP 10 Trace — 5 R-SEGPHOS 14 83 10 6 (R, R)-DIOP 1 95 56 7 (R, R)-BDPP 0.5 94 82 8 (R, R)-Chiraphos 10 Trace — a Reaction conditions: 1a (0.30 mmol), 2a (0.9 mmol), ZnI2 (0.03mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%) and a bidentate ligand (6.5 mol%) or monodentate ligand (11.0 mol%).b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. 表 3 添加剂筛选a
Table 3. Screening of additives

Entry Additive Time/h Yieldb/% eec/% 1 CuI 1.4 67 81 2 CuBr 2.3 98 80 3 CuOTf 26 Trace — 4 AgBF4 13 Trace — 5 AgOTf 13 Trace — 6 Zn(OTf)2 13 Trace — 7 ZnI2 0.5 94 82 8 (n-Bu)4NI 2 96 77 9 — 1 95 66 a Reaction conditions: 1a (0.30 mmol), 2a (0.9 mmol), additives (0.03mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP (6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. 表 4 苯酚类底物适用性研究a
Table 4. Scope of phenols

Entry Phenol Time/h Yieldb/% eec/% 1 
0.5 94 82 2 d 
39 80 69 3 
1.5 92 82 4 
3.5 92 74 5 
2 96 81 6 
3 89 78 7 
12 84 78 8 
6 54 78 9 
0.5 72 76 10 
3 78 82 a Reaction conditions: 1a (0.30 mmol), 2a~2j (0.9 mmol), additives (0.03 mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP(6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 60 ℃. 表 5 氧杂苯并冰片烯类底物适用性研究a
Table 5. Scope of oxabenzonorbornadiene derivatives

Entry Oxabenzonorbornadiene Time/h Yieldb/% eec/% 1 
2 84 75 2 
31 90 80 3 
48 62 78 4 
29 88 85 5 d 
27 95 78 6 
2 85 80 a Reaction conditions: 1b~1g (0.30 mmol), 2a (0.9 mmol), additives (0.03 mmol), THF (2.0 mL), [Rh(COD)Cl]2 (2.5 mol%), (R, R)-BDPP(6.5% mol). b Isolated yield. c Determined by HPLC with a Chiralcel AD-H column. d React at 60 ℃. -
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