A new 1,3-dipolar cycloaddition reaction

Ochiai, Masahito; Obayashi, M.; Morita, Katsura

doi:10.1016/0040-4020(67)85128-7

Cited by 65 publications

(16 citation statements)

References 5 publications

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“…The reactiono fv ariousp rimary alcohols with benzyl phenyl sulfone (entries 13-30) also resulted in the highly E-selective formationo fs tyryl derivatives. Benzyla lcohols weres electively convertedt og ive the corresponding E-stilbenes with high isolated yields (83-93 %, entries [13][14][15][16][17][18][19][20]. Naphthyl alcohols (entries 21,22) and heteroaromatic alcohols with furanyl, thienyl, pyridinyl, and benzo [1,3]dioxonyl groups (entries23-26) were also converted to the corresponding styryl derivatives in good to high yields (84-94 %).…”

Section: Pt/c-catalyzedd Irect Olefination Of Alcoholswith Sulfonesmentioning

confidence: 99%

Direct Olefination of Alcohols with Sulfones by Using Heterogeneous Platinum Catalysts

Siddiki

Touchy

Kon

et al. 2016

Chemistry A European J

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Carbon-supported Pt nanoparticles (Pt/C) were found to be effective heterogeneous catalysts for the direct Julia olefination of alcohols in the presence of sulfones and KOtBu under oxidant-free conditions. Primary alcohols, including aryl, aliphatic, allyl, and heterocyclic alcohols, underwent olefination with dimethyl sulfone and aryl alkyl sulfones to give terminal and internal olefins, respectively. Secondary alcohols underwent methylenation with dimethyl sulfone. Under 2.5 bar H2, the same reaction system was effective for the transformation of alcohol OH groups to alkyl groups. Structural and mechanistic studies of the terminal olefination system suggested that Pt(0) sites on the Pt metal particles are responsible for the rate-limiting dehydrogenation of alcohols and that KOtBu may deprotonate the sulfone reagent. The Pt/C catalyst was reusable after the olefination, and this method showed a higher turnover number (TON) and a wider substrate scope than previously reported methods, which demonstrates the high catalytic efficiency of the present method.

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Section: Pt/c-catalyzedd Irect Olefination Of Alcoholswith Sulfonesmentioning

confidence: 99%

Direct Olefination of Alcohols with Sulfones by Using Heterogeneous Platinum Catalysts

Siddiki

Touchy

Kon

et al. 2016

Chemistry A European J

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“…-MS.: 531 ( M + , < l), 516 (3), 288 (4), 272 (2), 270 (9, 258 (18), 244 (18), 243 4,02-2,76 (m, 7H). 3400, 1695, 1490, 1455, 1385, 1272, 1157, llOOsh, 1077); 4,82(dx d, J=3,5/6,8, H-C(2')); 4,68(dx d, J=3,2/6,8, H-C(3')); 3,95 (.y (8), 199 (13), 198 (58), 180(11), 170(24), 156 (5), 145 (5), 144 (62), 143 (3), 142 (6), 141 (8), 140 (7), 129 (7), 128 (3), 127 (4), 126 (31), 116 (56), 115 (17), 114 (8), 113 (23), 100 (8), 98 (37), 87 (lo), 86 (5% 85 (20), 84 (15), 73 (lo), 72 (34), 71 (40), 69 (23), 68 (loo), 59 (80), 57 (351, 55 (30), 43 (100), 41 (23).…”

Section: I~h Z~n O~mentioning

confidence: 99%

“…Problemstellung. - 21 1,82 (13; 5 3 2,88 (7,5) 1,06 1,03 1,46 23 1,Y3 (13; 6) 3,03 (7) 1,08 1, 33 1,52 (1,58)…”

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Synthese und Umwandlungen von Isoxazolidin‐Nucleosiden

Vasella

1977

Helvetica Chimica Acta

101

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Synthesis and Transformations of Isoxazolidine-Nucleosides SummaryReaction of the oxime 12 with formaldehyde, acetaldehyde or acetone in the presence of methacrylic acid methylester leads in a highly stereoselective 1,3 dipolar cycloaddition of the corresponding nitrones to the protected isoxazolidine ribosides 13, 14, 20, 21 and 26 (Scheme 1 and 2).Using a new, mild procedure to effect detritylation, the cycloaddition products were transformed into the alcohols 16-19, 22-25 and 27.Cleavage of a mixture of the glycosides 16 and 17 yielded the N-unsubstituted isoxazolidine 29 in 65% optical purity while the cleavage of 27 gave optically pure 28.Alternatively, the isoxazolidine ribosides 13, 14, 16-18 and 26 were transformed via reductive cleavage of the isoxazolidine N-0 bond and subsequent lactamization into the corresponding pyrrolidinone-ribosides 30, 33, 35, 42, 49 and 50, the ribitolyl pyrrolidinones 31, 34, 36-39 and 43-46 (see Scheme 4) and the ribitolyl isoxazolidine 47.Einleitung. -Die Bedeutung der Nucleoside beruht auf den biologischen Eigenschaften, die sich sowohl bei natiirlich vorkommenden wie auch bei synthetisch hergestellten Vertretern finden. Beispiele dafiir sind das immunosuppressiv wirksame Bredinin (1) [ 1-31, das aus dem Kulturfiltrat von Eupenicillium brefeldianum isoliert wurde und das synthetisch hergestellte, antiviral wirksame Ribavirin (2) [4].

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“…18 Once formed, the nitrone was observed to undergo both inter-and intramolecular 1,3-dipolar cycloaddition (Scheme 2). Shortly thereafter, the Grigg group exploited this methodology for the synthesis of various nitrogen-containing heterocycles, further establishing the concept that nitrones could be readily formed by treating oximes with various electrophilic reagents.…”

Section: Synthetic Methodsmentioning

confidence: 99%