辛弗林衍生物的合成

以苯甲醚为起始原料,与乙酰氯发生付-克酰基化后脱甲基得到4-羟基苯乙酮,然后与液溴进行α-溴代得到2-溴-1-(4-羟苯基)乙酮,再与叔丁胺进行胺化得到1-(4-羟基苯基)-2-(叔丁基氨基)乙酮,最后用氢硼化钠还原合成目标产物1-(4-羟基苯基)-2-(叔丁基氨基)乙醇,总收率约为42.3%。     

4-羟基联苯-4′-甲酸-L-2-甲基丁醇酯的合成

以4-羟基联苯,4-羟基-4′-氰基联苯和手性L-2-甲基丁醇为原料,通过三条路线合成了铁电性液晶中间体4-羟基联苯-4′-甲酸-L-2-甲基丁醇酯.5步法(醚化、酰化、溴仿、水解和酯化)总收率35.6%;3步法(酰化、溴仿和酯化)总收率50.7%;而以4-羟基-4′-氰基联苯为原料的一步合成法收率64.4%.中间体和目标产物的结构经1H NMR和IR确证.     

取代邻羟基苯乙酮的简便绿色合成

以对甲(氯、溴)苯酚(1a-c)为起始原料经酰化得对甲(氯、溴)苯酚乙酯,再以BF3·2HAc为催化剂无溶剂条件下实现Fries重排,以77.3%-80.4%的收率分别得到了5-甲基(氯、溴)邻羟基苯乙酮(2a-c);应用环境友好的聚乙二醇-400为溶剂,N-氯(溴、碘)代丁二酰亚胺为卤代试剂对邻羟基苯乙酮进行卤代反应,以61.8%-92.4%的收率制备3,5-二氯(溴、碘)邻羟基苯乙酮(4a-c);以邻羟基苯乙酮为原料,硝酸铈铵(CAN)为绿色硝化试剂,分别以29.8%和63.9%的收率得到了3位和5位硝化产物1-(2-羟基-3-硝基苯基)乙酮、1-(2-羟基-5-硝基苯基)乙酮(5a-b)。以上制备过程具有反应条件温和、后处理简单、环境友好等优点,为制备取代邻羟基苯乙酮提供了简单且绿色的新方法。     

三(3,6-二氧杂庚基)胺催化合成异黄酮7-O-葡萄糖糖苷

分别以Friedel-Crafts反应和Hoesch反应制备的7-羟基异黄酮/7-羟基-4'-甲氧基异黄酮和5,7-二羟基-4'-甲氧基异黄酮/5,7-二羟基-4'-氯异黄酮为苷元,以三(3,6-二氧杂庚基)胺(TDA-1)为相转移催化剂,NaHCO3/KCl体系为碱性介质,研究了异黄酮类化合物与1-溴-2,3,4,6-O-四乙酰基-α-D-吡喃葡萄糖进行偶联反应制备糖苷的合成工艺,其结构经IR和1H NMR以及元素分析测试技术的确证,总收率分别为64%、61%、55%和58%.     

4-甲酰基苯基(2,3,4,6-O-四乙酰基)-β-D-葡萄糖苷衍生物的有效合成

为克服目前合成方法存在收率较低,反应时间长、产品分离困难等不足,本文以β-D-葡萄糖、乙酰溴为原料,经乙酰化、溴代反应合成了糖基体2,3,4,6-O-四乙酰基-α-D-溴代葡萄糖,再与4-羟基苯甲醛衍生物经糖苷化反应合成了5种4-甲酰基苯基(2,3,4,6-O-四乙酰基)-β-D-葡萄糖苷衍生物。在合成4-甲酰基苯基(2,3,4,6-O-四乙酰基)-β-D-葡萄糖苷衍生物的过程中,采用10%(质量分数) Na OH溶液为缚酸剂,三(3,6-二氧杂庚基)胺(TDA-1)为相转移催化剂,反应物的收率为61%～69%,并应用核磁共振技术确定了产品的结构。该方法具有产品收率较高,反应温和、操作简单等优点。     

褪黑激素的合成与表征

以吲哚为起始原料,经4步反应合成了褪黑激素(MLT) 吲哚(1)在甲醇中羟基化得到5-羟基吲哚(2),(2)同2-氯乙胺在乙酸乙酯中进行胺乙基化反应得到5-羟基色胺(3),(3)与硫酸二甲酯在甲苯中对羟基进行醚化,得到5-甲氧基色胺(4),(4)经乙酰化得到产物MLT,收率80%     

相转移催化合成黄豆黄苷的研究

以4-甲氧基间苯二酚和对羟基苯乙腈通过Hoesch反应制备的7,4'-二羟基-6-甲氧基异黄酮(黄豆黄素)为苷元,以三(3,6-二氧杂庚基)胺(TDA-1)为相转移催化剂,碳酸氢钠/氯化钾体系为碱性介质,研究了黄豆黄素与1-溴-2,3,4,6-O-四乙酰基-α-D-吡喃葡萄糖进行偶联反应制备大豆异黄酮黄豆黄苷的合成工艺,糖苷化反应收率为77%,结构经IR和1H NMR以及元素分析加以确证.     

磷酸特地唑胺的合成新方法

以(5R)-3-(4-溴-3-氟苯基)-5-羟甲基噁唑烷-2-酮为起始原料,在[PdCl₂(dppf)]·CH₂Cl₂催化下与联硼酸频那醇酯反应得到硼化物,继而与5-溴-2-(2-甲基-2H-四唑-5-基)吡啶进行Suzuki反应得到特地唑胺,收率82.9%。 分别考察了催化体系对硼化反应和Suzuki反应的影响,确定了较佳的反应条件。 特地唑胺与二苄基N,N-二异丙基亚磷酰胺反应得到二苄基保护的磷酸特地唑胺,随后经Pd/C脱苄得到磷酸特地唑胺,总收率66.2%。     

D-脯氨酸催化的(3S,4S)-4-氨基-3-羟基-5-苯基戊酸衍生物的合成

报道了一条合成(3S,4S)-4-氨基-3-羟基-5-苯基戊酸(Ahppa)衍生物的新路线。以氨基保护的L-苯丙氨酸为起始原料,依次经Weinreb胺缩合、还原、aldol缩合及溴仿4步反应合成了3个Ahppa衍生物,总收率5.8%~6.7%,其结构经¹H NMR, ¹³C NMR和ESI-MS确证。对反应条件进行了探讨,结果表明：催化剂D-脯氨酸用量对反应收率影响不大,对立体选择性影响较大;氨基上保护基体积较大有利于提高反应立体选择性。     

6-溴-N-芳基噻吩[2,3-d]并嘧啶-4-胺类化合物的合成新方法

研究了6-溴-N-[3-氯-4-(3-氟苄氧基)苯基]噻吩[2,3-d]并嘧啶-4-胺的合成新方法.以相对廉价的2,5-二羟基-1,4-二噻烷和丙二腈为原料,依次通过Gewald反应、芳环溴代、缩合、环合以及Dimroth重排四步反应得到目标产物6-溴-N-[3-氯-4-(3-氟苄氧基)苯基]噻吩[2,3-d]并嘧啶-4-胺,总产率为56.9%.用1H NMR,IR,MS和HRMS对产物进行了结构表征.并应用该方法,合成了一系列的6-溴-N-芳基噻吩[2,3-d]并嘧啶-4-胺类化合物.研究表明该方法具有原料易得、操作简便、收率较高,且产物容易分离纯化等优点.     

Synthesis of extended polyphosphacumulenes

Addition of two equivalents of (Me(3)Si)(2)CLiCl to the C-[(diphenyl) (diisopropylamino)phosphonio]-P-(diisopropylamino)phosphaalkene 2 affords the 1sigma(4),3sigma(3)-diphosphabuta-1,2,3-triene E1 in 55 % yield. Derivative E1 was fully characterized, including a single-crystal X-ray diffraction study. Alkylation of E1 with methyl trifluoromethanesulfonate gives rise to the first C-phosphonio-bis(methylene)phosphorane 5, which was isolated in 84 % yield. Because the second carbon center is also nucleophilic, cumulene E1 reacts as a "pincer" with BF(3)OEt(2), leading to the formation of a novel four-membered PCBC heterocycle 6 with a betaine-like structure. Addition of three equivalents of P-[diphenyl(diisopropylamino)]methylene phosphorane to (diisopropylamino)dichlorophosphane, followed by addition of one equivalent of CCl(4), and subsequent deprotonation with lithium hexamethyldisilazide gave rise to 1sigma(4),3sigma(3),5sigma(4)-triphosphapenta-1,2,3,4-tetraene F1, which was isolated in 62 % yield.     

An effective and convenient synthesis of cordycepin from adenosine

Cordycepin is a purine nucleoside analog with potent and diverse biological activities. Herein, we designed two methods to synthesize cordycepin. One method mainly converted the 3′-OH group into an iodide group and further dehalogenation to yield the final product. Although this method presented a short synthetic procedure, the synthesis had a low overall yield, resulting in only 13.5% overall yield. To improve the overall yield of cordycepin, another synthetic route was studied, which consisted of four individual steps: (1) 5′-OH protection (2) esterification (3) -O-tosyl (-OTs) group removal (4) deprotection. The key step in the synthetic method involved the conversion of 5′-O-triphenylmethyladenosine to 3′-O-tosyl-5′-O-triphenylmethyladenosine, using LiAlH₄ as reducing agent. The main advantages of this route were an acceptable total product yield and the commercial availability of all starting materials. The optimal reaction conditions for each step of the route were identified. The overall yield of cordycepin obtained from adenosine as the starting material was 36%.     

A study on the synthesis of calix[4 and 6]arenes using alternately arranged phloroglucinols and p-tert-butylphenols

A method for the synthesis of calix[4 and 6]arenes with two or three alternately arranged phloroglucinols and p-tert-butylphenols was studied using "3+1" and "5+1" approaches, compared to a simple one-pot synthesis based on a "1+1" approach. By using Yb(OTf)3 as a catalyst, each calix[4 and 6]arenes was afforded, in an overall yield of 20.7% and 11.8% in the "3+1" and "5+1" approaches, respectively, and 24.6% and 19.9% using a "1+1" approach with chlorobenzene and toluene as refluxing solvents, respectively.     

Synthesis of an octasubstituted galactose zinc(II) phthalocyanine

4,5-Bis(1,2:3,4-di-O-isopropylidene-α-d-galactopyranos-6-yl)phthalonitrile (3) was prepared by S_NAr reaction of diacetone galactose 1 and 4,5-difluorophthalonitrile (2) in 96% yield. Cyclotetramerization of 3 was achieved via its isoindoline derivative 4, affording the peripherally octasubstituted galactose zinc(II) phthalocyanine 5 in 29% yield. Deprotection of 5 gave the highly water soluble octasubstituted galactose zinc(II) phthalocyanine 6 in 81% yield which will be applied as a photosensitizer in photodynamic therapy.     

The Asymmetric Syntheses of Methyl <small>D</small>-Digitoxoside, <small>L</small>-Oleandrose and <small>L</small>-Cymarose from Methyl Sorbate, an Achiral Precursor

The addition of 4?eq of chloral to osmundalactone (4S,5R)-4 gave quantitative formation of the hemiacetal derivative (4S,5R)-8, which was treated with methane sulfonic acid to afford the intramolecular Micheal addition product (+)-(3S,4S,5R)-9 possessing a 3,4-cis-dihydroxy-δ-lactone in 78% overall yield from (4S,5R)-4. The obtained (+)-(3S,4S,5R)-9 was subsequently converted to methyl D-digitoxoside (pyranoside) (12) in 13% overall yield and methyl D-digitoxoside (furanoside) (12) in 20% overall yield. The reaction of benzyl-osmundalactone (4R,5S)-3 and MeOH in the presence of Amberlyst A-26 as a basic catalyst gave 3,4-trans-δ-lactone (－)-(3S,4R,5S)-20 in 28% yield and 3,4-cis-δ-lactone (－)-(3R,4R,5S)-21 in 45% yield. Dibal-H reduction of (－)-(3S,4R,5S)-20 followed by catalytic hydrogenation gave L-oleandrose (6) in 86% overall yield, while Dibal-H reduction of (－)-(3R,4R,5S)-21 followed by catalytic hydrogenation provided L-cymarose (7) in 85% overall yield.     

三种O－异戊烯基苯丙素类天然产物的首次合成

以香草醛为起始原料，经O－异戊烯基化、Witting反应、水解、还原、氧化等 反应步骤，首次合成了三种苯丙素天然产物boropinalA（1），boropinalC（2） boropinicAcid（3）,有化合物结构均由核磁共振氢谱，质谱及红外光谱确证，用 X射线衍射法测定了3的晶体及分子结构。     

An efficient preparation, crystal structures, and properties of monocarbenium-ion compounds stabilized by 3-guaiazulenyl and anisyl groups

Reaction of guaiazulene (1) with 2-methoxybenzaldehyde (2) in methanol in the presence of hexafluorophosphoric acid at 25 °C for 2 h gives (3-guaiazulenyl)(2-methoxyphenyl)methylium hexafluorophosphate (5a) in 93% yield. Similarly, reaction of 1 with 3-methoxybenzaldehyde (3) or 4-methoxybenzaldehyde (4) under the same reaction conditions as for 2 affords (3-guaiazulenyl)(3-methoxyphenyl)methylium hexafluorophosphate (6) (91% yield) or (3-guaiazulenyl)(4-methoxyphenyl)methylium hexafluorophosphate (7) (97% yield). The crystal structures as well as the spectroscopic, electrochemical, and chemical properties of these monocarbenium-ion compounds, possessing interesting resonance forms, stabilized by the 3-guaiazulenyl and anisyl (i.e., 2-, 3-, or 4-methoxyphenyl) groups are reported.     

Stereoselective construction of the 1,1,1-trifluoroisopropyl moiety by asymmetric hydrogenation of 2-(trifluoromethyl)allylic alcohols and its application to the synthesis of a trifluoromethylated amino diol

The asymmetric hydrogenation of a series of 2-(trifluoromethyl)allylic alcohols 1a-g catalyzed by a BINAP-Ru(II) diacetate complex gave the corresponding products 2a-g in high yield (>90% yield) and high diastereoselectivity (>95% de). The asymmetric hydrogenation of 2-(trifluoromethyl)allylic alcohols provided an efficient stereoselective method to construct the 1,1,1-trifluoroisopropyl moiety. Based on the asymmetric hydrogenation of the 2-(trifluoromethyl)allylic alcohol 5a prepared by the reaction of (R)-2,2-dimethyl-1,3-dioxolane-4-carboxaldehyde with 3,3,3-trifluoroisopropenyllithium, (2R,3S,4R)-4-trifluoromethyl-1-aminopentane-2,3-diol 9 was synthesized in 36% overall yield over five steps.     

Concise synthesis of prenylated and geranylated chalcone natural products by regiospecific iodination and Suzuki coupling reactions

Four natural chalcones bearing prenyl or geranyl groups, i.e., isobavachalcone (1), bavachalcone (2), xanthoangelol (3), and 2′,4′,4-trihydroxy-5′-geranylchalcone (isoxanthoangelol, 4) were synthesized by using a regio-selective iodination and the Suzuki coupling reaction as key steps. Among them, the first total synthesis of 2′,4′,4-trihydroxy-5′-geranylchalcone was achieved in 36% overall yield. Comparing with the reported methods based on C-alkylation or O-alkylation followed by Claisen rearrangement to introduce the side chain, this new strategy capitalizes on a precious regiochemical control during iodination. The overall yields for the synthesis of the first three chalcones were improved from 17% to 53%, 12% to 35%, and 28% to 50%, respectively.