Transpositions de structures a caractere dialllique—IV

Structure–Activity Relationship in the Domain of Odorants Having Marine Notes

“…The same comment is valid for a synthetic access via the dinitrile 15 [11]. A shorter alternative is possible via the 3,4-dihydro-3-methylene-2H-1,5-benzodioxepines 16, by using 3-chloro-2-(chloromethyl)prop-1-ene [7] [12] or a palladium-catalyzed condensation with an allylic biscarbonate [13] followed by an oxidation step.…”

“…13 C-NMR: 15.5 (q); 28.0 (t); 75.5 (t); 75.8 (t); 120.0 (d); 120.7 (d); 123.1 (d); 140.3 (s); 146.2 (s); 148.1 (s); 204.8 (s). MS: 192 (100, M þ ), 177 (29), 150 (12), 149 (88), 136 (6), 135 (20), 123 (9), 122 (6), 121 (7), 108 (16), 105 (9), 94 (5), 91 (18), 89 (7), 80 (15), 79 (32), 78 (8), 77 (29), 67 (5), 65 (13), 63 (11), 55 (6), 51 (18), 39 (13), 27 (7).…”

“…13 C-NMR: 13.8 (q); 24.4 (t); 37.1 (t); 75.5 (t); 75.8 (t); 120.5 (d); 120.6 (d); 123.7 (d); 138.7 (s); 146.2 (s); 148.0 (s); 204.8 (s). MS: 206 (50, M þ ), 178 (12), 177 (100), 149 (30), 135 (10), 123 (7), 121 (6), 105 (6), 91 (9), 79 (7), 77 (19), 65 (12), 63 (7), 55 (9), 51 (11), 39 (9), 27 (7).…”

Conception, Characterization and Correlation of New Marine Odorants

“…Schirmann et al [10] employed 3-chloro-2-(chloromethyl)prop-1-ene in a synthesis of 3-methylene-3,4-dihydro-2H-benzo[b] [1,4]dioxepine, which they prepared in 62% yield from pyrocatechol. An alternative reagent for this transformation of diols to 6-methylene-1,4-dioxepanes is tris-ω,ω,ω-bromomethylacetophenone as reported by Nerdel, Mamluk and Weyerstahl.…”

An Environmentally Friendly Oxidation System for the Selective Oxygenation of Aldimines to Oxaziridines with Anhydrous TBHP and Alumina‐Supported MoO3 as a Recyclable Heterogeneous Catalyst

“…[2] Oxygenation of imines is an important synthetic transformation as oxaziridines are synthetically important building blocks that find wide application in asymmetric synthesis, [3][4][5] in the preparation of biologically active compounds [6,7] and extensively used as nitrogen [8,9] and oxygen [10,11] transfer reagents in various synthetically important reactions. A variety of oxidizing agents such as m-CPBA, [12][13][14][15][16] Ac 2 O/H 2 O 2 , [17] urea/H 2 O 2 , [18] [19,20] tert-amyl hydroperoxide [21] and molecular oxygen [22,23] in the presence of transition metals were used to accomplish this transformation. However, most of these methods are associated with drawbacks such as harsh reaction conditions, the use of aldehydes as a sacrificial agent, the formation of side products, poor yields and difficult work up procedures, which leaves room to develop an efficient and simple process for the oxygenation of imines to oxaziridines.…”