952
S. D. Zanatta, B. Jarrott, and S. J. Williams
tautomerization to varying degrees, leading to complex NMR
spectra.
OCH3 (enol)), 3.77 (s, 3H, OCH3 (keto)), 3.79 (s, 3H, OCH3
(enol)), 3.99 (s, 2H, CH2CO2), 5.63 (s, 1H, CH (enol)), 7.52
(s, 2H, Ar (enol)), 7.65 (s, 2H, Ar (keto)), 12.53 (s, 1H, OH).
δC (100 MHz, CDCl3) 23.77, 23.83 ((CH3)2CH), 26.56, 26.59
(CH(CH3)2), 45.8 (CH2CO2), 51.3, 52.3, 62.2 (OCH3), 86.1
(CH (enol)), 122.3, 125.1, 129.4, 132.3, 142.1, 142.5, 157.5,
159.6 (12C, Ar), 168.1 (enol C), 172.0, 173.5 (CO2), 191.7
(ketone CO). νmax/cm−1 2963, 2872, 1743, 1682, 800. m/z
(HRMS-ESI+) [M + H]+ Anal. Calc. for C17H25O4: 293.1747.
Found 293.1745.
3-(4-Methoxy-3,5-dimethylphenyl)-β-oxo-propanoic Acid
Methyl Ester 10b2
The title compound was prepared by the representative proce-
dure starting from 1-(4-methoxy-3,5-dimethylphenyl)ethanone
(9b2). After flash chromatography (10% EtOAc/petrol), 10b2
was obtained as a yellow oil (935 mg, 60%). δH (500 MHz,
CDCl3) 2.24 (s, 6H, ArCH3 (enol) × 2), 2.25 (s, 6H, ArCH3
(keto) × 2), 3.68 (s, 3H, OCH3 (enol)), 3.69 (s, 3H, OCH3
(keto)), 3.70 (s, 3H, OCH3 (keto)), 3.72 (s, 3H, OCH3 (enol)),
3.90 (s, 2H, CH2 (keto)), 5.54 (s, 1H, CH (enol)), 7.38 (s,
2H, Ar (enol)), 7.56 (s, 2H, Ar (keto)), 12.46 (s, 1H, OH). δC
(100 MHz, CDCl3) 16.0 (ArCH3), 45.2 (CH2), 52.1 (OCH3),
59.4 (OCH3), 85.9 (CH (enol)), 126.6, 129.4, 130.9, 131.2,
131.4, 161.6 (Ar), 167.9 (enol C), 171.4 (CO2), 191.4 (ketone
CO). νmax/cm−1 2952, 1744, 1680, 1597, 1137, 1004, 889.
m/z (HRMS-ESI+) [M + Na]+ Anal. Calc. for C13H16NaO4:
259.0941. Found 259.0938.
3-(4-Ethoxy-3,5-diisopropylphenyl)-β-oxo-propanoic Acid
Methyl Ester 10d3
The title compound was prepared by the representative proce-
dure starting from 1-(4-ethoxy-3,5-diisopropylphenyl)ethanone
(9d3). After flash chromatography (10% EtOAc/petrol), 10d3
was obtained as a yellow oil (600 mg, 64%). δH (400 MHz,
CDCl3) 1.20 (d, J 6.8, 12H, (CH3)2CH), 1.42 (t, J 7.0, 3H,
CH2CH3), 3.28 (septet, J 7.0, 2H, (CH3)2CH × 2), 3.71 (s,
3H, OCH3), 3.80 (q, J 7.0, CH2CH3), 3.95 (s, 2H, CH2CO2),
7.68 (s, 2H, Ar). δC (100 MHz, CDCl3) 14.7 (CH2CH3), 23.8
(CH(CH3)2), 28.0 (CH(CH3)3), 47.9 (CH2CO2), 51.6 (OCH3),
71.4 (CH3CH2), 123.5, 127.7, 136.1, 153.1 (6C, Ar), 168.1
(CO2), 192.6 (CO). νmax/cm−1 2963, 1743, 1682, 1622, 1461,
1290, 1163, 800. m/z (HRMS-ESI+) [M + H]+ Anal. Calc. for
C18H27O4: 307.1904. Found 307.1906.
3-(4-Ethoxy-3,5-dimethylphenyl)-β-oxo-propanoic Acid
Methyl Ester 10b3
The title compound was prepared by the representative pro-
cedure starting from 1-(4-ethoxy-3,5-dimethylphenyl)ethanone
(9b3). After flash chromatography (10% EtOAc/petrol), 10b3
was obtained as a yellow oil (971 mg, 68%). δH (400 MHz,
CDCl3) 1.40 (t, J 6.8, 3H, CH2CH3), 2.27 (s, 6H, ArCH3 × 2
(enol)), 2.29 (s, 6H, ArCH3 × 2 (keto)), 3.72 (s, 3H, OCH3
(keto)), 3.76 (s, 3H, OCH3 (enol)), 3.88 (q, J 6.8, 2H, OCH2),
3.93 (s, 3H, OCH3 (keto)), 5.57 (s, 1H, CH (enol)), 7.42 (s,
2H, Ar (enol)), 7.59 (s, 2H, Ar (keto)). δC (100 MHz, CDCl3)
15.6, 16.3, 16.4 (ArCH3,CH2CH3), 45.4 (CH2CH3), 51.2 (enol,
OCH3), 52.3 (OCH3), 67.9, 68.0 (OCH2), 86.0 (CH (enol)),
126.6, 128.3, 129.4, 131.2, 131.3, 131.5, 158.9, 161.0 (12C,
Ar), 168.1 (enol C), 171.6, 173.5 (CO2), 191.6 (ketone CO).
νmax/cm−1 2980, 2956, 1746, 1680, 1483, 1140, 1108, 987, 662.
m/z (HRMS-ESI+) [M + Na]+ Anal. Calc. for C14H18NaO4:
273.1097. Found 273.1089.
3-(3,5-Di-(tert-butyl)-4-methoxyphenyl)-β-oxo-propanoic
Acid Methyl Ester 10e2
Thetitlecompoundwaspreparedbytherepresentativeprocedure
starting from 1-(3,5-di-(tert-butyl)-4-methoxyphenyl)ethanone
(9e2). After flash chromatography (10% EtOAc/petrol), 10e2
was obtained as a brown oil (490 mg, 96%). δH (400 MHz,
CDCl3) 1.43 (s, 18H, C(CH3)3 × 2), 3.69 (s, 3H, OCH3), 3.71
(s, 3H, OCH3), 3.74 (s, 3H, OCH3), 3.79 (s, 3H, OCH3), 4.00
(s, 2H, CH2CO2), 5.59 (s, 1H, CH (enol)), 7.66 (s, 2H, Ar), 7.87
(s, 2H, Ar), 12.53 (OH). δC (100 MHz, CDCl3) 31.7 (C(CH3)3),
35.8, 35.9 (C(CH3)3), 45.8 (CH2), 51.2, 52.3, 64.4 (OCH3), 85.9
(CH (enol)), 124.6, 127.4, 130.5, 144.0, 144.4, 164.6 (12C, Ar),
168.1 (CO2), 191.8 (CO). νmax/cm−1 2956, 2876, 1744, 1680,
1619, 1203, 883. m/z (HRMS-ESI+) [M + Na]+ Anal. Calc. for
C19H28O4Na: 343.1885. Found 343.1877.
3-(3,5-Diethyl-4-methoxyphenyl)-β-oxo-propanoic Acid
Methyl Ester 10c3
Thetitlecompoundwaspreparedbytherepresentativeprocedure
starting from 1-(3,5-diethyl-4-methoxyphenyl)ethanone (9c3).
After flash chromatography (10% EtOAc/petrol), 10c3 was
obtained as a yellow oil (619 mg, 76%). δH (400 MHz, CDCl3)
1.24(t, J7.6, 6H, CH2CH3), 2.69(q, J7.6, 4H, CH2CH3), 3.73(s,
3H, OCH3), 3.76 (s, 3H, OCH3), 3.97 (s, 2H, CH2CO2), 7.66 (s,
2H,Ar). δC (100 MHz, CDCl3) 14.6 (CH2CH3), 22.8 (CH2CH3),
45.6 (CH2CO2), 52.3, 61.0 (OCH3), 125.0, 131.9, 137.6, 161.1
(6C,Ar), 168.1(CO2), 191.7(CO). νmax/cm−1 2968, 1742, 1680,
1005, 880, 803. m/z (HRMS-ESI+) [M + H]+ Anal. Calc. for
C15H20NaO4: 287.1254. Found 287.1252.
3-(3,5-Di-(tert-butyl)-4-ethoxyphenyl)-β-oxo-propanoic
Acid Methyl Ester 10e3
Thetitlecompoundwaspreparedbytherepresentativeprocedure
starting from 1-(3,5-di-(tert-butyl)-4-ethoxyphenyl)ethanone
(9e3). After flash chromatography (10% EtOAc/petrol), 10e3
was obtained as a brown oil (511 mg, 55%). δH (400 MHz,
CDCl3)1.01(t, J7.2, 3H, CH2CH3), 1.02(s, 18H, C(CH3)3 × 2),
3.32 (s, 3H, CH3), 3.37 (q, J 7.2, 2H, CH2CH3), 3.56 (s,
2H, CH2CO2), 7.47 (s, 2H, Ar). δC (100 MHz, CDCl3) 14.6
(CH2CH3), 31.6 (C(CH3)3), 35.7 (C(CH3)3), 45.6 (CH2CO2),
52.1 (OCH3), 71.9 (CH2CH3), 127.4, 130.3, 144.2, 163.0 (6C,
Ar), 168.0 (CO2), 191.6 (CO). νmax/cm−1 2956, 1742, 1680,
1435, 1383, 1197, 733. m/z (HRMS-ESI+)[M + H]+ Anal. Calc.
for C20H31O4: 335.2217. Found 335.2217.
3-(3,5-Diisopropyl-4-methoxyphenyl)-β-oxo-propanoic
Acid Methyl Ester 10d2
Thetitlecompoundwaspreparedbytherepresentativeprocedure
starting from 1-(3,5-diisopropyl-4-methoxyphenyl)ethanone
(9d2). After flash chromatography (10% EtOAc/petrol), 10d2
was obtained as a yellow oil (595 mg, 58%). δH (400 MHz,
CDCl3) 1.25 (d, J 7.0, 12H, (CH3)2CH × 2), 3.36 (septet, J 7.0,
2H, (CH3)2CH × 2), 3.75 (s, 3H, OCH3 (keto)), 3.75 (s, 3H,
3-(3,5-Di-(tert-butyl)-4-(methoxymethoxy)phenyl)-
β-oxo-propanoic Acid Methyl Ester 8
The title compound was prepared by the representative proce-
dure starting from 1-(3,5-di-(tert-butyl)-4-(methoxymethoxy)