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1.
The fluorescent excited state of the 2-naphthoxide ion (1) is quenched by aliphatic and aromatic halides according to an electron-transfer mechanism, with generation of the corresponding alkyl and aryl radicals by a concerted or consecutive C-X bond fragmentation reaction. Whereas bromo- and iodobenzene follow a concerted ET mechanism (C-X, BDE control), 1-bromonaphthalene exhibits a stepwise process (pi LUMO control). The photoinduced reaction of anion 1 with 1-iodoadamantane (2) in DMSO affords substitution products on C3, C6, and C8, 1-adamantanol, 1-adamantyl 2-naphthyl ether, and adamantane (3.2, 13.2, 12.2, 2.8, 2.5, and 14.1% yields, respectively). A complex mixture is also observed in the photochemical reaction of neopentyl iodide (3) with anion 1, which renders substitution on C1, C3, C6, C8, and 2-naphthyl neopentyl ether (8.1, 1.3, 19.1, 31.1, and 2.8% yields, respectively). The absence of reaction in the dark and the inhibition of the photoinduced reaction by the presence of the radical traps di-tert-butylnitroxide (DTBN) and 1,4-cyclohexadiene are evidence of a radical chain mechanism for these substitutions. On the other hand, only coupling at C1 is achieved by the photostimulated reaction of anion 1 with iodobenzene (5), to afford 41.9% of 1-phenyl-2-naphthol and 5.4% of disubstitution product. The regiochemistry of these reactions can be ascribed to steric hindrance and activation parameters. 相似文献
2.
Neophyl radicals were generated by photoinduced electron transfer (PET) from a suitable donor to the neophyl iodide (1, 1-iodo-2-methyl-2-phenylpropane). The PET reaction of 1 with the enolate anion of cyclohexenone (2) afforded mainly the reduction products tert-butylbenzene (5) and the rearranged isobutylbenzene (6), arising from hydrogen abstraction of the neophyl radical (15) and the rearranged radical 16 intermediates, respectively. The photostimulated reaction of 1 with 2 in the presence of di-tert-butylnitroxide, as a radical trap, afforded adduct 10 in 57% yield. The photoinduced reaction of the enolate anion of acetophenone (3) with 1 gave the substitution products 11 (50%) and 12 (16%), which arise from the coupling of 3 with radicals 15 and 16, respectively. The rate constant obtained for the addition of anion 3 to radical 15 was 1.2 x 10(5) M(-)(1) s(-)(1), by the use of the rearrangement of this radical as a clock reaction. The anion of nitromethane (4) was almost unreactive at the initiation step, but in the presence of 2 under irradiation, it gave high yields (67%) of the substitution product 13 and only 2% of the rearranged product 14. When the ratio of 4 to 1 was diminished, it was possible to observe both substitution products 13 and 14 in 16% and 6.4% yields, respectively. These last results allowed us to estimate the coupling rate constant of neophyl radicals 15 with anion 4 to be at least of the order of 10(6) M(-)(1) s(-)(1). Although the overall quantum yield determined (lambda = 350 nm) for the studied reactions is below 1, the chain lengths (Phi(propagation)) for the reaction of 1 with anions 3 and 4 are 127 and 2, respectively. 相似文献
3.
The reactivity of -SC(NH)NH2 (1), MeCOS- (2), and PhCOS- (3) toward 1-naphthyl radicals was studied in DMSO. The photostimulated reaction of anions 1, 2, and 3 with 1-bromonaphthalene (4) after quenching with MeI renders 1-(methylthio)naphthalene (6) as a main product together with bis(1-naphthyl) sulfide (7) and naphthalene (5). The thioacetate ion (2) and thiobenzoate ion (3) were unreactive toward 4 as electron-donor under photostimulation; however, in the presence of potassium tert-butoxide anion (entrainment conditions), they gave the mentioned products 5, 6, and 7, after the addition of MeI. Quenching of the triplet state of 4 was assigned as the photoinduced initiation step, with a rate constant value of (4.6+/-0.5)x10(8) M-1 s-1 for tert-butoxide anion and a rough estimated value of (8+/-7)x10(7) M-1 s-1 for anion 1. By using hydrogen abstraction from DMSO as the competitive reaction, the absolute rate constants for the addition of anions 1, 2, and 3 to 1-naphthyl radicals have been determined to be 1.0x10(9), 1.2x10(9), and 3.5x10(9) M-1 s-1, respectively. This reactivity order is in agreement with the stability of the resulting radical anions (ArNu)*- (10-12)*-. The inhibition experiments of the photoinduced substitution reaction in the presence of radical scavengers and the global quantum yield higher than the unity are evidence of a radical chain mechanism for these substitution reactions by anions 1 and 2. Anion 3 adds to the 1-naphthyl radical, but is neither able to initiate nor to keep the propagation cycle. Evaluation of the electron-transfer driving forces for the reaction between (ArNu)*- and 4 together with the absence of a chain reaction for the anion 3 indicate that the propagation in the proposed mechanism is given by an acid-base reaction between the radical .C(O)Me or .C(NH)NH2 (13) and a base. 相似文献
4.
V. G. Tsypin V. V. Kachala B. I. Ugrak E. L. Golod 《Russian Journal of Organic Chemistry》2002,38(1):90-94
Adamantylation of indazole and its C-nitro derivatives with 1-hydroxyadamantane in mineral acids yields exclusively the corresponding 1-(1-adamantyl)indazoles via attack by 1-adamantyl cation on the protonated substrate. The oxidative alkylation with 1-iodoadamantane leads to formation of 1- and 2-(1-adamantyl)indazoles, the 2-isomer prevailing. 相似文献
5.
Nikola Basari? Margareta Horvat Kata Mlinari?-Majerski Axel G. Griesbeck 《Tetrahedron》2009,65(7):1438-15
Adamantyl-functionalized phthalimides were synthesized and the probability of intramolecular photochemical hydrogen atom abstraction in the solid state analyzed by X-ray crystallographic analyses. These analyses and solid-state photolyses showed that the parameters determining photochemical reactivity for typical carbonyl compounds in the solid state can also be extended to phthalimides. Only N-(2-adamantyl)phthalimide underwent a solid-state photochemical reaction, which is the first example in the phthalimide series. This reaction is regio- and stereoselective, resulting in an endo-alcohol. On the other hand, the photoreaction of N-(2-adamantyl)phthalimide in solution gives an exo-alcohol as the main product together with an endo-alcohol and a benzazepindione. 相似文献
6.
The gas phase reactions of the bridgehead 3-carboxylato-1-adamantyl radical anion were observed with a series of neutral reagents using a modified electrospray ionisation linear ion trap mass spectrometer. This distonic radical anion was observed to undergo processes suggestive of radical reactivity including radical-radical combination reactions, substitution reactions and addition to carbon-carbon double bonds. The rate constants for reactions of the 3-carboxylato-1-adamantyl radical anion with the following reagents were measured (in units 10(-12) cm(3) molecule(-1) s(-1)): (18)O(2) (85 +/- 4), NO (38.4 +/- 0.4), I(2) (50 +/- 50), Br(2) (8 +/- 2), CH(3)SSCH(3) (12 +/- 2), styrene (1.20 +/- 0.03), CHCl(3) (H abstraction 0.41 +/- 0.06, Cl abstraction 0.65 +/- 0.1), CDCl(3) (D abstraction 0.035 +/- 0.01, Cl abstraction 0.723 +/- 0.005), allyl bromide (Br abstraction 0.53 +/- 0.04, allylation 0.25 +/- 0.01). Collision rates were calculated and reaction efficiencies are also reported. This study represents the first quantitative measurement of the gas phase reactivity of a bridgehead radical and suggests that distonic radical anions are good models for the study of their elusive uncharged analogues. 相似文献
7.
Basarić N Horvat M Mlinarić-Majerski K Zimmermann E Neudörfl J Griesbeck AG 《Organic letters》2008,10(18):3965-3968
The photochemical reaction of N-(1-adamantyl)phthalimide (1) gives cleanly one product, the novel hexacyclic benzazepine derivative of 2,4-methanoadamantane 2. Its structure was characterized by spectroscopic methods and X-ray analysis and represent the first example of the 2-azahexacyclo[8.7.1.1 (1,4).0 (4,9).0 (11,16).0 (12,18)]nonadeca-4,6,8-triene skeleton. The product is formed by a domino process of two consecutive excited-state intramolecular gamma-hydrogen-transfer reactions. Base hydrolysis of the benzazepine 2 gives in high yield the keto derivative of the 1,2-substituted adamantane epsilon-amino acid 3. 相似文献
8.
There was no reaction of 7-iodobicyclo[4.1.0]heptane (7-iodonorcarane, 1) (exo-endo ratio of ca. 1) with acetophenone enolate ions 2 in DMSO at 25 degrees C; however, with the addition of SmI(2) or FeBr(2) and under the same experimental conditions, the substitution product 3 was obtained in 9% and 72% yields, respectively, with an exo-endo ratio of ca. 16 similar to the product ratio from photostimulated reactions. Thus, it seems that 7-norcaranyl radicals are intermediates of these reactions. With FeBr(2) at 60 degrees C the yield of 3 was as high as 90%. Reactions of 1 with the enolate ion of 2-naphthyl methyl ketone 4 induced by FeBr(2) gave substitution product 5 in 60% yield (96% of it the exo isomer). In competition experiments, 4 was 1.7 times more reactive than 2, and the anion of nitromethane (7) was 6.5 times more reactive than 2 toward 7-norcaranyl radicals. The reactions of 1-iodoadamantane (9) and neopentyl iodide (11) with carbanion 2 induced by FeBr(2) gave the substitution products in 85% and 92% yields, respectively. These observations indicate that all these reactions induced by FeBr(2) occur by the S(RN)1 mechanism. 相似文献
9.
N. V. Makarova A. A. Pimenov M. N. Zemtsova I. K. Moiseev 《Russian Journal of Organic Chemistry》2001,37(8):1099-1101
The Claisen-Schmidt reaction between 3-hydroxy-1-adamantyl methyl ketone and aromatic aldehydes (benzaldehyde and 2-thiophenecarbaldehyde) in 2-propanol catalyzed by 50% aqueous potassium hydroxide affords 1-(3-hydroxy-1-adamantyl)-3-R-2-propen-1-ones. The reaction of 3-hydroxy-1-adamantyl methyl ketone with ethyl formate and sodium in benzene gives rise to sodium enolate of 1-(3-hydroxy-1- adamantyl)-3-hydroxy-2-propen-1-one. The latter compound treated with amine hydrochlorides in 50% aqueous alcohol furnishes 1-(3-hydroxy-1-adamantyl)-3-NRR'-amino-2-propen-1-ones. 相似文献
10.
Koval'skaya S. S. Kozlov N. G. Dikusar E. A. 《Russian Journal of Organic Chemistry》2004,40(5):668-674
Reaction of 2-(3-hydroxy-3-methyl-1-butynyl)adamantan-2-ol with acetonitrile under Ritter reaction conditions is accompanied by isomerization and partial hydration where the water addition to the triple bond occurs nonselectively. As a result of reaction carried out in the presence of 8 equiv of sulfuric acid a mixture was obtained of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]-acetamide, and N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-1-oxo-3-butyl]acetamide in ~10:3:2 ratio. In the presence of 2 equiv of the acid the mixture obtained consisted of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]acetamide, and 1-(1-acetylamino-2-adamantyl)-3-methyl-2-buten-1-one in the same ratio. In Rupe reaction conditions we obtained instead of the expected ,-unsaturated ketones a mixture of 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-1-one and 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-2-one in a 5:3 ratio. 相似文献
11.
The interaction of the sodium salts of 3-(1-adamantyl)-1-hydroxy-1-propen-3-one and 4-(1-adamantyl)-1-hydroxy-1-buten-3-one with hydroxylamine, hydrazine, and guanidine leads to the synthesis of 5-(1-adamantyl)-5-hydroxy- and 5-(1-adamantylmethyl)-5-hydroxy-2-isoxazolines, 3-(1-adamantyl)- and 3-(1-adamantylmethyl)pyrazoles, 3-(1-adamantyl)-2-phenylpyrazole, and 4-(1-adamantyl)-2-amino- and 4-(1-adamantylmethyl)-2-aminopyrimidines. 相似文献
12.
Reaction of 2-adamantyl chloroformate under a variety of solvolytic conditions leads to 2-adamantyl chloride accompanied by solvolysis products, some with and some without retention of the CO(2) unit. For example, in 100% ethanol, only 4.8% 2-adamantyl chloride is formed with the mixed carbonate (88%) being the dominant product, and in 100% 2,2,2-trifluoroethanol, the products are both formed with loss of CO(2), 59% of the chloride and 41% of the ether. With exclusion of the specific rates in 100% and 90% ethanol and methanol, a good Grunwald-Winstein plot against Y(Cl) values (solvent ionizing power) is obtained, with a slope of 0.47 +/- 0.03. The results are compared with those reported earlier for 1-adamantyl chloroformate and isopropyl chloroformate and mechanistic conclusions are drawn. 相似文献
13.
M. L. Petrov A. A. Shchipalkin V. A. Kuznetsov B. N. Viktorov 《Russian Journal of Organic Chemistry》2010,46(8):1214-1218
Treatment of ethyl 2-[1-(1-admantyl)ethylidene]hydrazine-1-carboxylate with thionyl chloride gave 4-(1-adamantyl)-1,2,3-thiadiazole
which readily underwent decomposition by the action of strong bases with formation of alkali metal 2-(1-adamantyl)ethynethiolates.
The latter were brought into reactions with proton donors and benzyl halides. 相似文献
14.
Two 2,3-dihydro-2-(4-pyridinyl)-1H-isoindoles 2a,b have been synthesized by the reaction of isoindoline with 4-chloropyridines. In addition, a number of 1-alkyl-2,3-dihydro-2-(4-pyridinyl)-1H-isoindoles 2c-h were obtained from 2-(4-pyridinyl)phthalimide (5). The addition of alkyl Grignard reagents to 5 gave 1-alkylhydroxyisoindolones 6a-f which, in two cases 6a,b , were dehydrated and subjected to three separate reductions to give targets 2c,d . In three cases, the intermediate hydroxyisoindolones 6c-e were reduced in one step to the target compounds 2c-g with lithium aluminum hydride-aluminum chloride. When 6f , the product of the addition of phenyl Grignard to 5 , was subjected to these conditions, a hydroxyisoindoline 7 was obtained which was further reduced to 2h with triethylsilane-trifluoroacetic acid. The lithium aluminum hydride-aluminum chloride conditions were successfully applied to the synthesis of a 1-benzyl-4-piperidine derivative 21. 相似文献
15.
A. A. Shchipalkin M. L. Petrov V. A. Kuznetsov 《Russian Journal of Organic Chemistry》2011,47(8):1209-1213
The reaction of 4-(1-adamantyl)-1,2,3-thiadiazole with potassium tert-butylate followed by treating with acetyl chloride and amine results in the formation of 1-adamantylthioacetic acid amides
in moderate or good yields. 相似文献
16.
The reaction of 3-(1-adamantyl)-1-chloro-2-propanone with amines [diethylamine, (1-adamantyl)methylamine, p-toluidine, and piperidine] in diethyl ether at room temperature involves the Favorskii rearrangement and yields N,N-disubstituted amides of 3-(1-adamantyl)propanoic acid. 相似文献
17.
The reaction of 2-(2 pyridytcarbonyl)benzoic acid with thionyl chloride affords an unexpected product of the intramolecular acylation of the pyridine nitrogen atom, namely, 6,11-dioxo-6,11-dihydrobenzo[blquinotizinium chloride. At the same time, 2-(2-quinotylcarbonyl)benzoic acid forms the expected cyclic acid chloride, namely, 3-(2-gitinotyl)-3-chlorophthalide in this reaction. Both compounds acylate ammonia and primary amines, including those with bulky alkyl groups (tert-butyl, 1-adamantyl, and 1,1,3,3-tetramethylbutyl) with the formation of 2-R-3-hydroxy-3-(2pyridyl- or 2-quinolyl)isoindolines. The protonation of the pyridine nitrogen atom of N-(1,1,3,3-tetramethylbutyl)-2-(2pyridylcarbonyl)benzamide, obtained in the open amide form, is accompanied by the closing of the isoindotinone ring; the deprotonation is accompanied by ring opening.Riga Technical University, Riga LV-1048. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 499–504, April, 1994. Original article submitted March 17, 1994. 相似文献
18.
A reaction of 2-iodophenol and 2-iodoanisole with 1-adamantanol in trifluoroacetic acid gives the corresponding 4-(1-adamantyl) derivatives. Similar adamantylation of 4-iodophenol and 4-iodoanisole is accompanied by migration of the iodine atom from para- to ortho-position, giving 4,6-di(1-adamantyl)-2-iodophenol and 4-(1-adamantyl)-2-iodoanisole, respectively, as the reaction products. 相似文献
19.
Kalinin VN Rys EG Tyutyunov AA Starikova ZA Korlyukov AA Ol'shevskaya VA Sung DD Ponomaryov AB Petrovskii PV Hey-Hawkins E 《Dalton transactions (Cambridge, England : 2003)》2005,(5):903-908
The first carborane triflates, namely, 1-trifluoromethanesulfonylmethyl-o-carborane (2) and 1,2-bis(trifluoromethanesulfonylmethyl)-o-carborane (7), were obtained in high yields in the reactions of 1-hydroxymethyl-o-carborane (1) or 1,2-bis(hydroxymethyl)-o-carborane (6) with triflic anhydride (Tf2O) in CH2Cl2 in the presence of pyridine. When an excess of pyridine is employed, 1-o-carboranylmethylpyridinium triflate (3), which retains a closo-icosahedral structure, or a pyridinium salt (4) with a zwitterionic nido-dicarbaundecaborate anion are obtained from 1, while the nido compound 8 is formed from 6. The reaction of compound 2 or 7 with excess pyridine also gave 3 or 8, respectively. Compound 2 proved to be a convenient carboranylmethylating agent which reacts with nucleophiles (e.g., potassium phthalimide, PPh3 or KCN) to give the corresponding substitution products N-[(o-carboranyl-1-yl)methyl]phthalimide (9), o-carboranylmethylphosphonium salt 10, and 1-cyanomethyl-o-carborane (11). All compounds were characterized by 1H and 11B NMR spectroscopy. The structures of compounds 4, 7 and 8 were established by X-ray analysis. 相似文献
20.
Filipiak P Camaioni DM Fessenden RW Carmichael I Hug GL 《The journal of physical chemistry. A》2006,110(38):11046-11052
The reaction of the alpha-hydroxyalkyl radical of 2-propanol (1-hydroxy-1-methylethyl radical) with nitrite ions was characterized. A product of the reaction was assigned as the adduct nitro radical anion, [HO-C(CH(3))(2)NO(2)](*-). This radical was identified using time-resolved electron spin resonance (TRESR). The radical's magnetic parameters, the nitrogen hyperfine coupling constant (a(N) = 26.39 G), and its g-factor (2.0052) were the same as those of the nitro radical anion previously discovered in (*)OH spin-trapping experiments with the aci-anion of (CH(3))(2)CHNO(2). Production of [HO-C(CH(3))(2)NO(2)](*-) was determined to be 38% +/- 4% of the reaction of (CH(3))(2)C(*)-OH with nitrite. The reason why this fraction was less than 100% was rationalized by invoking the competitive addition at oxygen, which forms [HO-C(CH(3))(2)ONO](*-), followed by a rapid loss of (*)NO. Furthermore, by taking this mechanism into account, the bimolecular rate constant for the total reaction of (CH(3))(2)C(*)-OH with nitrite at reaction pH 7 was determined to be 1.6 x 10(6) M(-1) s(-1), using both decay traces of (CH(3))(2)C(*)-OH and growth traces of [HO-C(CH(3))(2)NO(2)](*-). This correspondence further confirms the nature of the reaction. The reaction mechanism is discussed with guidance by computations using density functional theory. 相似文献