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1.
《Tetrahedron: Asymmetry》2007,18(19):2365-2376
Stereoselective [3+2] cycloadditions of trimethylenemethane (TMM) to the exocyclic CO and CN double bonds of (1S,3EZ,4R)-3-arylimino-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ones gave the corresponding spiro[bicyclo[2.2.1]heptane-2,2′-furan] and spiro[bicyclo[2.2.1]heptane-3,2′-pyrrolidine] derivatives. Further stereoselective reductions of the CN or CO bond in these cycloadducts furnished new chiral amines, diamines, and a new aminoalcohol. All cycloadditions and reductions of the CN double bonds took place from the less hindered endo-face of the (1S,3EZ,4R)-3-arylimino-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ones, exclusively, thus giving the corresponding products in 100% de. The structures were determined by NMR, NOESY spectroscopy, and by X-ray diffraction.  相似文献   

2.
《Tetrahedron: Asymmetry》2007,18(23):2746-2757
Stereoselective inverse-demand [4+2] cycloadditions of 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine and dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate to 4′-methylenedihydro-3′H-spiro[bicyclo[2.2.1]heptane-2,2′-furans] and 4′-methylene-1′-(4-nitrophenyl)spiro[bicyclo[2.2.1]heptane-3,2′-pyrrolidine] were studied. Cycloadditions took place stereoselectively at the exocyclic CC double bonds to give novel 11:14-isopropylidene-14-methyl-2,3-diaza-8-oxadispiro[5.1.5.2]pentadecane and 11:14-isopropylidene-11-methyl-2,3,8-triazadispiro[5.1.5.2]pentadecane derivatives in 50–98% de. The structures of the novel dispiro compounds were determined by NMR techniques, NOESY spectroscopy and X-ray diffraction.  相似文献   

3.
Abstract

In the present investigation, the authors could obtain a new series of spiranes (1) through the reaction of the high potential quinone tetrachloro-o-benzoquinone with 2-aryl-3-phenyl-3H-quinazoline-4-thiones. Thus, 2,3-diphenyl- (2a), 2-p-tolyl-3-phenyl- (2b) and 2-p-anisyl-3-phenyl- (2c)-3H-quinazoline-4-thiones react readily with tetrachloro-o-benzoquinone, in boiling toluene, to give the corresponding spiro-1,3-benzodioxole-2,4′-(3′H)-quinazolines (1a-c), respectively.  相似文献   

4.
酸催化莰烯与二醇的羟烷氧基化反应是合成标题化合物的可行路线。前人所用酸性催化剂有离子交换树脂及路易斯酸 BF_3·Et_2O。松原义治等报道用离子交换树脂催化茨烯或三环烯分别与乙二醇、1,2-丙二醇反应获得相应的醚,醚化产率分别为42%、33%。Fujioka,Futoshi 等以 BF_3·Et_2O 为催化剂,使莰烯与1,3-丁二醇反应获得产率为34%的醚。迄  相似文献   

5.
N-Boc-protected 8-azaspiro[bicyclo[3.2.1]octane-3,2′-oxirane] reacted with primary aliphatic amines through opening of the epoxide ring with formation of the corresponding amino alcohols which were converted into N-chloroacetyl derivatives. The latter underwent cyclization to N-Boc-protected 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones by the action of sodium hydride in DMF, and subsequent treatment with hydrogen chloride in ethyl acetate afforded 8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-one hydrochlorides.  相似文献   

6.
5-, 2-Methylbicyclo[2.2.1]hept-2-enes, 2-methylenebicyclo[2.2.1]heptane were synthesizedby a new procedure, and their transformations in a flow system over stationary layer of aluminosilicatecatalyst were studied at various temperatures. At 150-400°C these compounds undergo isomerization which is accompanied by -migration of hydrogen. The isomerization mechanism is discussed in terms of formation of classical carbocations, not invoking nonclassical carbenium ion.  相似文献   

7.
1 INTRODUCTION Organic phosphine compounds always attract great interest for their unique properties and extensive uses in biochemistry, pesticide chemistry and synthetic organic chemistry. In the last two decades, much attention has been paid to phosphorus-containing olefin and acetylenic compounds for their applications in transition metal chemistry, asymmetric catalysis and photorearrang- ement [1~7 ]. Previously, we have reported the crystal structure of a novel host compound which …  相似文献   

8.
Abstract

Besides the common cyclisation reactions between divalent electrophiles such as Soc12, SC12, etc. and 2,2′-alkylidene-bisphenols 1 with selective attack by the two oxygens yielding dibenzo[d,g][1,3,2]dioxathiocines [1] we observed previously an unusual cyclisation of 1 with S2CI2 with a nucleophilic attack by the ortho- and para-carbon atoms (C(2) and C(4)) of bisphenol 1 [2]. We now report a new type of cyclocondensation reaction of 4,4′,6,6′-tetrasubstituted 2,2′-alkylidene-bisphenols 1 with ClSCOCl affording spiro[1,3-benzoxathiepin-4(5H),1′-cyclohexa[2,4]dien]-2,2′-diones 2 together with the cyclic carbonates 3. The structures of the products were elucidated mainly by l3C-NMR- and 1H-NMR-spectroscopy. The mode of formation of the novel spiro thiocarbonates 2 resp. the known carbonates 3 [3] is discussed.  相似文献   

9.
The preparation of bicyclo[2.2.1] (E)-allylsulfones starting from the corresponding (Z)-vinylsulfones is described. Starting from 2,3-bis(phenylsulfonyl)norbornadiene 1, the Michael addition of organometallic reagents followed by the base catalyzed isomerization affords (E)-allylsulfones in high yields. The procedure allows to obtain vinylidenic norbornenes which are characteristic nuclei of valuable biologically active compounds.  相似文献   

10.
本文报道以缺铝氢型丝光沸石催化莰烯或三环烯与几种环醇, 如环戊醇、环乙醇、四氢糖醇、苯甲醇、苯乙醇、2-甲基苯乙醇等烷氧基化反应的结果。  相似文献   

11.
The development of new catalyst-free green and efficient protocol to access 5′-thioxospiro[indoline-3,3′-[1,2,4]triazolidin]-2-ones/spiro[indoline-3,3′-[1,2,4]triazolidine]-2,5′-diones, potential privileged scaffolds for drug discovery, is disclosed. Key feature of this methodology is the dual use of glycerol—a recyclable, bioorganic compound, as a solvent cum promoter. Other highlights include use of inexpensive reagents, mild reaction conditions, operational simplicity, short reaction time, no need for chromatographic purification, and high yields.  相似文献   

12.
Irradiation of (E,E)-arylidene-β-ionones in the presence of oxygen leads to the formation of 8-[β-arylethenyl]-2,2,6-trimethyl-7,9,10-trioxa-tricyclo[6.2.2.01,6]dodec-11-enes (3). However, prolonged irradiation in the presence of oxygen leads to their conversion to 6-hydroxy-1,7,7-trimethyl-2-oxa-bicyclo[4.4.0]dec-4-en-3-one (4), apparently proceeding through addition of oxygen to the side chain π-bond in 3.  相似文献   

13.
The keto and gem-ester functionalities of cyclohexanonedicarboxylates (1) offer a facile route for the synthesis of 5,7-diarylspiro[4,5,6,7-tetrahydrobenzo[d][1,2,3]selena/thiadiazole-6,5′-(hexahydropyrimidine)]-2′,4′,6′-triones (6 and 8) and -2′-thioxo-4′,6′-diones (7 and 9). The new compounds were characterized by IR, NMR, and CMR spectral data. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 17–23, 1999  相似文献   

14.

The reaction of indol-2,3-diones ( 1a–i ) with 5-aminoindazole ( 2 ) has resulted in the formation of hitherto unknown 3-(indazol-5-yl)iminoindol-2-ones ( 3a–i ) in quantitative yields which, on 1,3-dipolar cyclocondensation with mercaptoacetic acid ( 4 ), has afforded a series of new spiro heterocycles, 3′-(indazol-5-yl) spiro[3H, indol-3, 2′ -thiazolidine]-2,4′-diones* ( 5a–i ).  相似文献   

15.
近年来,我们曾报道了莰烯-三环烯在氢型丝光沸石催化下与开链醇及二醇等进行烷氧基化反应的结果。最近,Scheidll,Fran报道用浓硫酸催化莰烯与环戊醇反应,合成exo-1,7,7-三甲基双环[2.2.1]庚基环戊醚。  相似文献   

16.
2′-Oxo-1′,2′-dihydrospiro[cyclopropane-1,3′-indole]-2,2,3,3-tetracarbonitriles reacted with oxygencentered nucleophiles to form addition products at the cyano groups with conservation of the three-membered ring. Reactions of the title compounds with alcohols required the presence of base catalyst, and the products, 2-amino-4,4-dialkoxy-2′-oxo-1′,2′-dihydrospiro[3-azabicyclo[3.1.0]hex-2-ene-6,3′-indole]-1,5-dicarbonitriles, were converted into the corresponding 2-imino-2′,4-dioxospiro[3-azabicyclo[3.1.0]hexane-6,3′-indole]-1,5-dicarbonitriles and 2,2′,4-trioxospiro[3-azabicyclo[3.1.0]hexane-6,3′-indole]-1,5-dicarbonitriles by the action of acetic and sulfuric acids, respectively. The reactions with ketone oximes occurred in the absence of a catalyst, yielding 2-amino-4,4-bis(alkylideneaminooxy)-2′-oxo-1′,2′-dihydrospiro[3-azabicyclo[3.1.0]hex-2-ene-6,3′-indole]-1,5-dicarbonitriles. The reactions with thiols, aliphatic amines, and anilines were accompanied by opening of the three-membered ring. In the reactions with triphenylphosphine and thiols 2-(2-oxo-2,3-dihydro-1H-indol-3-ylidene)malononitrile was obtained, while morpholine and N,N-dimethylaniline gave rise, respectively, to 3,3-diaryl-and 3,3-dimorpholino-1H-indol-2(3H)-ones and tri- and dicyanoethylene derivatives.  相似文献   

17.
18.
绝大部份商品环氧树脂皆由双酚与环氧氯丙烷缩合而得,其最明显的缺点是粘度较大和耐温性能较差。近年来,在国外有不少报告,某些环氧化多烯可以避免这些缺点。但关于含双环[2.2.1]庚烷环的环氧化物则很少研究。本文报告有关这类环氧化物的合成及其固化的研究结果。作者按下列方式合成含双环[2.2.1]庚烷环的双环氧化物:  相似文献   

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