Oxygenation of Simple Olefins through Selective Allylic C−C Bond Cleavage: A Direct Approach to Cinnamyl Aldehydes

Abstract

An ovel metal-free allylic CÀC s-bond cleavage of simple olefins to give valuable cinnamyl aldehydes is reported. 1,2-Aryl or alkylmigration through allylic C À Cbond cleavage occurs in this transformation, which is assisted by an alkyl azide reagent. This method enables O-atom incorporation into simple unfunctionalized olefins to construct cinnamyl aldehydes.T he reaction features simple hydrocarbon substrates, metal-free conditions,and high regio-and stereoselectivity. Scheme 1. Allylic CÀCbond cleavage.

Catalytic, Enantioselective Syn-Diamination of Alkenes

“…An analytical sample was obtained by dissolution of a portion (100 mg) of the material in a minimal amount of pentane/diethyl ether (4:1, ~1 mL) and slow evaporation (~1 d) of the solution at room temperature. The resulting large, clear, pale-yellow rectangular prisms were collected with a spatula, broken up with a glass stir rod, and sonicated in pentane (1 mL 3 H,HC(15,16)), 3 H,HC(6,14)), 6.83 (d, J = 8.4 Hz, 1 H, HC 7 atmosphere. THF (25 mL) was added, followed by 2-naphthoyl chloride (3.37 g, 17.7 mmol, 3.00 equiv) against argon back-flow.…”

“…Following General Procedure III, N,N'-bis-(toluenesulfonyl)urea 1 (368 mg, 1.00 mmol), diselenide catalyst 9 (41.0 mg, 0.0500 mmol, 0.0500 equiv), NaF (42.0 mg, 1.00 mmol, 1.00 equiv), 2,4,6-Me 3 PyF + BF 4 -(295 mg, 1.30 mmol, 1.30 equiv), and trans-β-methylstyrene 10a 15, 313.1 (27), 314.1 (17), 315.1 (14), 405.1 (72), 406.1 15 10, 265.1 (19), 286.1 (19), 343.0 (55), 344.0 (11), 345.0 (54), 346.0 (11), 405.1 (17), 419.1 (67), 420.1 (19), 469.1 (18), 498.1 (22), 500.1 (21)…”

“…Following General Procedure III, N,N'-bis-(toluenesulfonyl)urea 1 (368 mg, 1.00 mmol), diselenide catalyst 9 (41.0 mg, 0.0500 mmol, 0.0500 equiv), NaF (42.0 mg, 1.00 mmol, 1.00 equiv), 2,4,6-Me 3 PyF + BF 4 -(295 mg, 1.30 mmol, 1.30 equiv), and cinnamyl chloride 10g (183 mg, 1.20 mmol, 1.20 equiv) in MeCN (5.0 mL, 0.20 M) were allowed to react for 24 h. The resulting suspension was worked up as described in the general procedure and purified by column chromatography (silica, 3 cm ø × 12 cm column) eluting with hexanes/EtOAc 14, 198.1 (30), 260.1 (13), 299.1 (38), 301.1 (13), 302.1 (19), 405.1 (39), 454.1 (51), 455.1 (14), 456.1 (19) Preparation of ((4S,5R)-2-Oxo-5-phenyl-1,3-ditosylimidazolidin-4-yl)methyl Acetate (11h)…”

“…Following General Procedure III, N,N'-bis-(toluenesulfonyl)urea 1 (368 mg, 1.00 mmol), diselenide catalyst 9 (41.0 mg, 0.0500 mmol, 0.0500 equiv), NaF (42.0 mg, 1.00 mmol, 1.00 equiv), 2,4,6-Me 3 PyF + BF 4 -(295 mg, 1.30 mmol, 1.30 equiv), and (E)-1-(3-(benzyloxy)prop-1en-1-yl)-4-fluorobenzene 10l (291 mg, 1.20 mmol, 1.20 equiv) in MeCN (5.0 mL, 0.20 M) were allowed to react for 24 h. The resulting suspension was worked up as described in the general procedure and purified by column chromatography (silica, 3 cm ø × 12 cm column)) eluting with 6), 3 H,HC(13,14)), 4 H,HC(12,17)), 7.11 (t,J = 8.7 Hz,4 H,HC(5,22) 2), 3.75 (dd, J = 9.9, 3.2 Hz, 1 H, HC(9)), 3.62 (dd, J = 9.9, 6.5 Hz, 1 H, H'C(9)), 2.44 (s,3 H,HC(19)), 2.37 (s,3 H,HC(24)). 6), 5 H,HC(9,10,11,26)), 3 H,HC(18,19)), 3 H,HC(13,17)), 7.16 (d,J = 8.4 Hz,2 H,HC(22) 82.9 (100), 84.9 (65), 86.9 (11), 91.1 (37), 155.0 (15), 210.0 (34), 212.0 (32), 343.0 (60), 344.1 (10), 345.0 (57).…”

“…rolapitant, 10 an antiemetic agent for chemotherapy patients; 9 and antiproliferative agents such as nutlin-3. 11 Furthermore, many different chiral, enantioenriched auxiliaries, ligands, and catalysts for organic synthesis are derived from vicinal diamines; 12,13 including Noyori enantioselective hydrogenation catalysts, 14 N-heterocyclic carbenes, 15 and various ligands for asymmetric additions of organometallic reagents. 13,16 Many of these chiral diamines are still most frequently obtained in enantioenriched form by classical resolution, 17,18 stereocontrolled transformations of enantioenriched starting materials, 7,19 or functional group interconversion of amino acids and other chiral pool materials.…”