用环加成反应合成含氟杂环化合物的研究

综述了近年来利用一些新型的含氟砌块，通过它们的环加成反应来高效地合成 含氟杂环化合物的研究，其中包括以下两个部分：(1)用1，3—偶极环加成反应合 成五元含氟杂环化合物；(2)用杂原于Diels-Alder反应合成六元含氟杂环化合物．     

双乙烯酮在杂环化学中的应用

双乙烯酮是最重要的乙酰乙酰化试剂，同时由于双乙烯酮具有多个反应中心，也被广泛用于杂环化合物的合成。本文总结了近十年来双乙类酮在杂环化学中的应用进展，参考文献38篇。     

含氮杂环及其衍生物的氮氧化方法研究进展

含氮杂环及其衍生物中的N－氧化反应是合成许多精细化工产品，如日用化学 品、医药、农药的重要反应，但该反应选择性较高，只要求在杂环氮上进行氧化而 不影响分子其它部位，从氮杂环及其衍生物应用不同氧化剂选择性氧化综述了该类 化合物的N－氧化反应。     

杂环合成中的氮杂Wittig反应

氮杂Wittig反应是杂环化合物的一个新的合成方法.本文阐述了羰基通过叠氮化物和三价膦形成的亚胺基膦的作用, 以氮杂Wittig反应的方式, 合成含氮杂环化合物的进展.     

α-重氮羰基化合物在合成五元杂环化合物中的新应用

本文综述了α-氮羰基化合物在合成五元杂环化合物方面新的研究成果，分为四大类：类卡宾对X－H键的插入反应；类卡宾时π键的反应；经由isomnchnone的反应；经由叶利德的反应．     

环链转移反应及其在合成杂环化合物中的应用

概括了环链转移反应的类型、机理,同时综述了环链转移反应在合成取代杂环化合物中的应用。     

1,3,2-氧氮磷杂环戊烷衍生物(Ⅱ)——2-二乙氨基-3-取代甲酰基-1,3,2-氧氮磷杂环戊烷衍生物的合成及其性质研究

用六乙基亚磷酰胺与N-(β-羟基乙基)取代甲酰胺进行成环反应,合成了一系列新的有机磷杂环化合物,2-二乙氨基-3-取代甲酰基-1,3,2-氧氮磷杂环戊烷,然后与硫作用生成2-硫逐代衍生物,亦可不经分离一步完成上述反应。     

稠杂环化合物的研究（Ⅹ）—3—芳基—6—苯甲酰氨基均三唑并[3…

本文利用３－芳基－４－氨基－５－巯基－１，２，４－均三唑和苯甲酰异硫氰酸酯在无水丙酮中反应，得到一系列３－芳基－６－苯甲酰氨基均三唑并［３，４－ｂ］－１，３，４－二噻二唑。用元素分析、ＩＲ、＾１Ｈ ＮＭＲ和ＭＳ确定了其结构，提出了可能的反应机制。并对其代表产物２ｈ进行了初步的抗菌和除草实验。     

杂氮硅三环成环反应的研究

本文报导了与硅原子直接相连的有机基团(R)对杂氮硅三环成环速率的影响。利用气相色谱检测成环反应的产物之一——乙醇的生成速率和数量,并同与硅相连的R基团对成环反应速率的影响作比较。实验结果表明五种杂氮硅三环成环速度顺序为Cl_2CH—>ClCH_2—>ClCH_2CH_2CH_2—>CH_2=CH—>CH_3—,这与理论推断相符。     

3-(1-氢多氟烯基)-1-氧代-2，4，1-苯并噁嗪与双亲核试剂反应合成含氟杂环化合物

本文研究了3-(1-氢多氟烯基)-1-氧代-2，4，1-苯并噁嗪1与几种双亲核试剂的反应。化合物1与乙二胺反应生成7-氟烷基-1，4-二氮杂卓[1，2-d]喹唑啉-11-酮；在吡啶溶剂中与盐酸羟胺反应得到了2-氟烷基异噁唑[3,2-b]并喹唑啉-9-酮；与邻苯二胺反应得到2-氟烷基苯并咪唑类化合物。     

Enantio- and diastereoselective stepwise cyclization of polyprenoids induced by chiral and achiral LBAs. A new entry to (-)-ambrox, (+)-podocarpa-8,11,13-triene diterpenoids, and (-)-tetracyclic polyprenoid of sedimentary origin

An enantio- and diastereoselective stepwise cyclization of polyprenoids induced by Lewis acid-assisted chiral Br?nsted acids (chiral LBAs) and achiral LBAs is described. In particular, the absolute stereocontrol in the initial cyclization of polyprenoids to form an A-ring induced by chiral LBAs and the importance of the nucleophilicity of the internal terminator in polyprenoids for the relative stereocontrol in subsequent cyclization are demonstrated. (-)-Ambrox was synthesized via the enantioselective cyclization of (E,E)-homofarnesyl triethylsilyl ether with tin(IV) chloride-coordinated (R)-2-(o-fluorobenzyloxy)-2'-hydroxy-1,1'-binaphthyl ((R)-BINOL-o-FBn) and subsequent diastereoselective cyclization with CF(3)CO(2)H.SnCl(4) as key steps. Protection of (E,E)-homofarnesol by a triethylsilyl group increased the enantioselectivity of chiral LBA-induced cyclization and both the chemical yield and diastereoselectivity in the subsequent cyclization. The enantioselective cyclization of homo(polyprenyl)arenes possessing an aryl group was also induced by (R)-BINOL-o-FBn.SnCl(4). Several optically active podocarpa-8,11,13-triene diterpenoids and (-)-tetracyclic polyprenoid of sedimentary origin were synthesized (75-80% ee) by the enantioselective cyclization of homo(polyprenyl)benzene derivatives induced by (R)-BINOL-o-FBn.SnCl(4) and subsequent diastereoselective cyclization induced by BF(3).Et(2)O/EtNO(2) or CF(3)CO(2)H .SnCl(4).     

Regioselective unusual formation of spirocyclic 4-{2'-benzo(2',3'-dihydro)furo}- 9-methyl-2,3,9-trihydrothiopyrano[2,3-b]indole by 4-exo-trig aryl radical cyclization and rearrangement

4-(2'-Bromoaryloxymethylene)-9-methyl-2,3,9-trihydrothiopyrano[2,3-b]indoles under tri-n-butyltin hydride mediated aryl radical cyclization furnished exclusively the 4-{2'-benzo(2',3'-dihydro)furo}-9-methyl-2,3,9-trihydrothiopyrano[2,3-b]indoles in excellent yield (75-80%) via 4-exo-trig cyclization, opening of the oxetene ring, and 5-endo-trig cyclization.     

7-endo selective aryl radical cyclization onto enamides leading to 3-benzazepines: concise construction of a cephalotaxine skeleton

Bu3SnH-mediated radical cyclizations of 2-(2-bromophenyl)-N-ethenylacetamide gave 6-exo cyclization product 15 as the major product, whereas N-[2-(2-bromophenyl)ethyl]-N-ethenylamides gave almost exclusively 7-endo cyclization products. These results indicated that the position of the carbonyl group on enamide played an important role in deciding the course of the cyclization. The 7-endo selective cyclization was applied to concise construction of a cephalotaxine skeleton.     

Palladium-catalyzed cyclization/carboalkoxylation of alkenyl indoles

Reaction of 1-methyl-2-(4-pentenyl)indole with a catalytic amount of PdCl2(CH3CN)2 (5 mol %) and a stoichiometric amount of CuCl2 (3 equiv) in methanol under CO (1 atm) at room temperature for 30 min led to cyclization/carboalkoxylation to form the corresponding tetrahydrocarbazole in 83% isolated yield as a single regioisomer. Palladium-catalyzed cyclization/carboalkoxylation of 2-(4-pentenyl)indoles tolerated substitution along the alkenyl chain and at the internal and cis-terminal olefinic positions. Palladium-catalyzed cyclization/carboalkoxylation tolerated a range of alcohols and was effective for the cyclization of 2-(3-butenyl)indoles, 3-(3-butenyl)indoles, 3-(4-pentenyl)indoles, and 2-(5-hexenyl)indoles.     

Some fatty acids having an O-heterocycle in their terminal positions. II. ω-(3-Coumarinyl)alkanoic acids and ω-(2-chromonyl)alkanoic acids

Some ω-3-coumarinyl)alkanoic acids 1a , n = 3-6 were synthesized by cyclization of corresponding ethyl o-formylphenyl alkanedioate 3 with DBU followed by hydrolysis. By a similar cyclization, some ω-(2-chromonyl)alkanoic acids 2a , n = 3-6 were also obtained from the cyclization of corresponding o-acetylphenyl ethyl alkanedioate 4 .     

Comparative study of anionic and radical cyclization for the preparation of 1,3-dimethylindans: highly stereoselective preparation of cis-1,3-disubstituted indans via intramolecular carbolithiation

[reaction: see text] The preparation of 1,3-dimethylindans from 4-(2-bromophenyl)-1-pentene (1) and 2-(2-iodo-1-methylethyl)styrene (2) substrates via radical-mediated cyclization and intramolecular carbolithiation has been investigated. Although cyclization of the radical derived from either substrate proceeds with modest selectivity for the cis-isomer, as does cycloisomerization of the aryllithium derived from substrate 1 (cis/trans approximately 2), intramolecular cyclization of the alkyllithium derived from substrate 2 is a highly cis-selective process (cis/trans = 12).     

Synthesis of (-)-aphanorphine using aryl radical cyclization

[structure: see text] The synthesis of (-)-aphanorphine was achieved by using Bu(3)SnH-mediated aryl radical cyclization of 1-benzyloxycarbonyl-2-(2-bromo-4-methoxyphenylmethyl)-2-methoxycarbonyl-4-(phenylthiomethylene)pyrrolidine, leading to exclusive formation of the 6-exo cyclization product.     

Synthesis of spiro[4.5]decane and bicyclo[4.3.0]nonane ring systems by self-cyclization of (Z)- and (E)-2-(trimethylsilylmethyl)pentadienal derivative

The two title carbon frameworks were synthesized utilizing a new type of iron-induced cyclization reaction of 2-(trimethylsilylmethyl)pentadienal. 2-Methylspiro[4.5]dec-2-en-1-one was obtained from (Z)- and (E)-4-cyclohexylidene-2-(trimethylsilylmethyl)but-2-enal. It was found that the (Z)-substrate isomerized to (E)-intermediate followed by cyclization to afford the initial product, 2-methylenespiro[4.5]dec-3-en-1-ol, which was isomerized to the above product. The cyclization of 4-(4-alkyl)cyclohexylidene-2-(trimethylsilylmethyl)but-2-enal proceeded stereoselectively. While, (E)-3-(cyclohex-1-en-1-yl)-2-(trimethylsilylmethyl)prop-2-en-1-al cyclized immediately affording 8-methylenebicyclo[4.3.0]non-9-en-7-ol. The corresponding (Z)-isomer gave several cyclization products as a complex mixture.     

Kinetic Features of the Synthesis of an Acid Corrosion Inhibitor, 5-Methyl-1,2,3,3a,4,8b-hexahydrocyclopent[b]indole

Kinetic features of thermal cyclization of 2-methyl-6-(cyclopent-2-enyl)aniline hydrochloride at 200-220°C were studied. The cyclization product shows a high performance as acid corrosion inhibitor.     

Platinum-catalyzed intramolecular alkylation of indoles with unactivated olefins

Reaction of 1-methy-2-(4-pentenyl)indole (1) with a catalytic amount of PtCl2 (2 mol %) in dioxane that contained a trace of HCl (5 mol %) at 60 degrees C for 24 h led to the isolation of 4,9-dimethyl-2,3,4,9-tetrahydro-1H-carbazole (2) in 92% yield. Platinum-catalyzed cyclization of 2-(4-pentenyl)indoles tolerated substitution at each position of the 4-pentenyl chain. Furthermore, the protocol was applicable to the synthesis of tetrahydro-beta-carbolinones and was effective for cyclization of unprotected indoles. 2-(3-Butenyl)indoles underwent platinum-catalyzed cyclization with exclusive 6-endo-trig regioselectivity. Mechanistic studies established a mechanism for the platinum-catalyzed cyclization of 2-alkenyl indoles involving nucleophilic attack of the indole on a platinum-complexed olefin.