Acyl transfer reactions with phosphine oxides: synthesis of E-homoallylic alcohols, cyclopropyl ketones, and γ-hydroxy ketones

CMPO-calix[4]arenes and the influence of structural modifications on the Eu(III), Am(III), Cm(III) separation

“…Oxalyl chloride (3.6 g, 2.4 mL, 0.028 mol) was carefully dropped to the solution of 4(diphenylphosphoryl)butyric acid (5.0 g, 0.017 mol) [19] and p-nitrophenol (2.41 g, 0.017 mol) in chloroform (100 mL) under nitrogen. The reaction mixture was stirred at 45 • C for 6 days.…”

3-tert-Butyldimethylsilyloxymethyl-2-lithio-2-phenylsulfonyloxirane as a glycidyl anion equivalent; preparation of terminal epoxy ketones

“…and T H F and the reaction mixture was warmed to -80 "C and stirred at that temperature for 15 min. The residue was purified by flash chromatography using 15 trans-2-Benzoyl-3-tert-butyldimethylsilyloxymethyl-2-phenylsulfunyloxirane 4k. The electrophile was benzoyl chloride (2 equiv.)…”

“…73-75 "C (Found: C, 60.9; H, 6.4. C22H2805SSi requiresC,61.1; H, 6.5%); v,,,(KBr)/cm-' 2930,2859,1682,1323, H, s), AB part of an ABX system (6,3.73,6,4.04, J A B 12.9, JAx 3.1, JBx2.8),4.18(1 H,m),7.37-7.71 (6H,m),7.75-7.81(2H,m)and 7.91-7.99 (2 H, m); m/z (FAB) 433 (MH+, 4%), 375 (3), 345 (l), 319 (I), 301 (ll), 205 (20), 125 (15), 105 (100) and 73 (41).…”

“…60-80 "C)-ethyl acetate as eluent to give the epoxy ketone If as a colourless oil (0.0085 g, 19%) (Found: MH', 157.0874. C8Hl,0, requires 157.0891); v,,,(film)/cm-' 3453, 2961, 2874 and 1717; 6H(200 MHz) 1.69-2.20 (8 H, m), 2.92 (1 H, dd, J6.7, 2.5), 3.04 (1 H, dd, J6.7,4.4), 3.42 (1 H, s) and 3.75 (1 H, dd, J4.4, 2.5); m/z (EI) 157 (MH+, 4%), 139 (15), 85 (loo), 67 (93), 41 (94) and 29 (68). General Procedure for the One-pot Ring-closure Reactions of the Oxiranes 4,Solid magnesium bromide-diethyl ether (1 -6 equiv.)…”

The chemistry of lithiated phosphine oxides: the stereoselective synthesis of alkene-4,5-diols

“…5 Phosphine oxides with γor δ-acyloxy groups, once lithiated 3, react intramolecularly to give the products of acyl transfer (Scheme 2). 6 The tetrahedral intermediate formed in the initial addition to the ester functionality can be trapped by the trimethylsilyl chloride within the reaction. 7 Ketones formed by the acyl-transfer process can be reduced diastereoselectively to syn-β-hydroxy phosphine oxides 4, which in turn give (E)alkenes stereospecifically by base mediated elimination.…”