Synthesis and Comparison of the Reactivity of Allyl Fluorides and ...

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Chapter Six
suspension of sodium acetylacetonate (1.5 cm 3 of a 0.32 M solution in THF, 0.49 mmol)
was added and the reaction mixture stirred at 0 ºC for 1 h. After which, the reaction was
quenched with water (5 cm 3 ), and extracted with diethyl ether (10 cm 3 ). The diethyl ether
extracts were then washed with water, dried over MgSO4 and solvent removed in vacuo to
give the product (59 mg, 66 %). δH 1.89 (3H, s, CH3), 1.92 (3H, s, CH3), 2.78 (1H, d, 3 JHH =
12.1 Hz, Ha), 3.55 (2H, dm, 2 JHH = 13.3 Hz, He and Hf), 3.67 (1H, m, Hd) 3.72 (1H, d, 3 JHH
= 6.7 Hz, Hb), 4.53 (1H, d, 2 JHH = 11.7 Hz, CHHAr), 4.57 (1H, d, 2 JHH = 11.7 Hz, CHHAr),
5.28 (1H, s, CHCO), 5.40-5.50 (1H, m, Hc), 7.20-7.32 (5H, m, ArH); δC 26.8 (CH3), 27.2
(CH3), 53.0 (CHCH2), 68.1 (OCH2), 70.0 (OCH2CH), 71.9 (ArCH2), 98.9 (CHCO), 109.6
(CHCH2), 126.6 (ArCH-4), 126.7 (ArCH-3), 127.4 (ArCH-2), 137.2 (ArC-1), 186.3 (CO),
187.0 (CO).
6.4.3 Preparation of dimethyl 2-(1-(benzoyloxy)but-3-en-2-yl)malonate (148)
The novel compound was prepared following the
method outlined by Hayashi et al. [17] A 50 cm 3 , two-
necked round-bottom flask was equipped with a
magnetic stirring bar and Rotaflo tap and attached to a
Schlenk line. After flame-drying under high vacuum, the flask was cooled and filled with
nitrogen. The flask was charged with bis[�-chloro–bis-(butenyl-(1,2,3-�)-
benzoate]dipalladium (83 mg, 0.13 mmol) and anhydrous THF (5 cm 3 ). The reaction
mixture was stirred at room temperature for 15 minutes, after which PPh3 (136 mg, 0.52
mmol) and sodium dimethylmalonate (81 mg, 0.52 mmol) were added and the mixture
stirred overnight. The formed precipitate was filtered off and solvent removed in vacuo to
give the crude product which was purified by column chromatography [hexane: ethyl
acetate (70:30)], affording the product as a colourless oil (7 mg, 37 %). δH 3.27 (1H, m,
Hd), 3.61 (1H, d, 3 JHH = 8.6 Hz, CH(COOMe)2), 3.65 (6H, s, CH3), 4.32 (1H, dd, 2 JHH =
11.0 Hz, 3 JHH = 5.9 Hz, He), 4.40 (1H, dd, 2 JHH = 11.3 Hz, 3 JHH = 5.9 Hz, Hf), 5.14 (1H, d,
3 JHH = 10.2 Hz, Hb), 5.20 (1H, d, 3 JHH = 17.2 Hz, Ha), 5.81 (1H, ddd, 3 JHH = 17.2 Hz, 3 JHH =
10.2 Hz, 3 JHH = 8.6 Hz, Hc), 7.38 (2H, tm, 3 JHH = 7.8 Hz, ArH-3), 7.50 (1H, tm, 3 JHH = 7.4
Hz, ArH-4), 7.95 (2H, dm, 3 JHH = 8.6 Hz, ArH-2); δC 43.0 (OCH2CH), 52.6 (CH(COOMe)2),
53.3 (CH3), 65.2 (OCH2), 119.1 (CHCH2), 128.3 (ArCH-3), 129.6 (ArCH-2), 129.9 (ArC-1),
133.1 (ArCH-4), 134.4 (CHCH2), 166.2 (ArC=O), 168.1 (C=O). m/z (EI + ) 306 ([M] + , 5 %),
175 ([M-CH(COOMe)2] + , 90 %). HRMS (EI) 306.10984 (C16H18O6 requires 306.10989).