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maintained for 12 h. The solution was diluted with 30 mL of H2O.
The layers were separated and the aqueous layer was extracted
with hexanes (3ꢂ30 mL). The combined organic layers were
washed with 30 mL of saturated aqueous NaCl, dried (Na2SO4),
filtered, and concentrated in vacuo. The resultant yellow oil was
purified by flash chromatography (98:2 hexanes/EtOAc) to afford
0.150 mmol), AgO2CCF3 (0.001 g, 0.005 mmol), and 0.7 mL of ben-
zene-d6. The reaction mixture was kept at ambient temperature for
3.5 h. The reaction mixture was filtered through Celite with CH2Cl2
and concentrated in vacuo. The resultant yellow oil was purified by
flash chromatography (hexanes) to afford 36 (0.022 g, 60%) as
a colorless oil: 1H NMR (500 MHz, CDCl3)
d
7.29–7.34 (m, 4H), 7.13–
7.15 (m, 1H), 4.33 (s, 1H), 3.48 (s, 3H), 3.31 (s, 3H), 1.10 (s, 9H), 0.91
(s, 9H); 13C NMR (125 MHz, CDCl3)
141.9, 128.2, 126.3, 125.6, 78.7,
22 (2.78 g, 52%) as a colorless oil: 1H NMR (400 MHz, CDCl3)
d 7.26–
7.39 (m, 5H), 5.58–5.59 (m, 1H), 4.61 (d, J¼12.0, 1H), 4.55 (d, J¼12.0,
d
1H), 3.95–3.97 (m, 1H), 1.72–1.97 (m, 5H), 1.71 (s, 3H), 1.25–1.28 (m,
58.9, 53.0, 28.6, 28.4, 22.4, 21.8; IR (thin film) 2936, 2858, 1599,
1493, 1474, 1109 cmꢁ1; HRMS (ESI) m/z calcd for C17H30NaO2Si
(MþNa)þ 317.1913, found 317.1922.
1H); 13C NMR (125 MHz, CDCl3)
d 139.2, 139.1, 128.4, 127.7, 127.4,
122.2, 72.7, 70.1, 30.3, 28.0, 23.8,19.4. 1H and 13C NMR spectroscopic
data matched those previously reported.27
4.1.7. Alkyl silane 38
4.1.3. Representative procedure for the synthesis of allylic silanes
(allylic silane 23)
To a J. Young NMR tube were added propionaldehyde diethyl
acetal (37) (20 mL, 0.125 mmol), silacyclopropane 10 (0.034 g,
To a Schlenck flask were added allylic ether 22 (0.202 g,
1.00 mmol), silacyclopropane 10 (0.270 g, 1.20 mmol), CuOTf$PhMe
(0.026 g, 0.050 mmol, 2:1 complex), and 7 mL of toluene. The
brown solution was then placed under an Ar atmosphere and
allowed to stir for 12 h, at which point the mixture was concen-
trated in vacuo. The resultant yellow oil was purified by flash
chromatography (hexanes) to afford 23 (0.278 g, 81%) as a colorless
0.150 mmol), AgO2OCF3 (0.001 g, 0.005 mmol), and 0.7 mL of ben-
zene-d6. The reaction mixture was kept at ambient temperature for
20 min. The reaction mixture was filtered through Celite with
CH2Cl2 and concentrated in vacuo. The resultant yellow oil was
purified by flash chromatography (hexanes) to afford 38 (0.017 g,
50%) as a colorless oil: 1H NMR (500 MHz, CDCl3)
d 3.92–3.80 (dq,
J¼9.9, 6.9, 1H and dq, J¼9.9, 6.9, 1H), 3.71 (dq, J¼8.6, 7.0, 1H), 3.32
(dq, J¼8.6, 7.0, 1H), 3.13 (dd, J¼7.5, 5.6, 1H), 1.78–1.79 (m, 2H), 1.10–
1.22 (t, J¼6.9, 3H and t, J¼7.0, 3H), 1.01–1.09 (s, 9H; s, 9H; and t,
oil: 1H NMR (400 MHz, CDCl3)
d 7.24–7.40 (m, 5H), 5.54–5.55 (m,
1H), 4.97–4.98 (m, 2H), 2.16–2.17 (m, 1H), 1.84–1.97 (m, 4H), 1.66–
1.75 (m, 1H), 1.64 (s, 3H), 1.40–1.45 (m, 1H), 1.10 (s, 18H); 13C NMR
J¼7.4, 3H); 13C NMR (125 MHz, CDCl3)
d 75.9, 67.9, 60.1, 28.9, 28.7,
(125 MHz, CDCl3)
d
142.0, 131.9, 128.4, 126.7, 125.8, 122.4, 66.0, 30.2,
26.0, 21.9, 21.5, 18.9, 16.2, 13.8; IR (thin film) 2974, 2859, 1474, 1117,
1086, 823 cmꢁ1; HRMS (ESI) m/z calcd for C15H34NaO2Si (MþNa)þ
297.2226, found 297.2232.
29.3, 29.1, 24.5, 24.4, 22.8, 22.7; IR (thin film) 2931, 2856, 1454,
1082, 910, 735 cmꢁ1; HRMS (APCI) m/z calcd for C22H36NaOSi
(MþNa)þ 367.2433, found 367.2437.
4.1.8. Allylic ether 39
4.1.4. Allylic ether 28
The representative procedure for the synthesis of aryl-protected
allylic alcohols was followed using 3-methyl-2-butene-1-ol
(1.02 mL, 10.0 mmol), 4-(trifluoromethyl)benzyl bromide (2.27 g,
9.5 mmol), NaH (0.312 g, 13.0 mmol), and 33 mL of THF for 12 h.
Purification by flash chromatography (98:2 hexanes/EtOAc) affor-
ded 39 (2.12 g, 87%) as a colorless oil: 1H NMR (500 MHz, CDCl3)
The representative procedure for the synthesis of aryl-protected
allylic alcohols was followed using trans-3-methyl-3-penten-2-ol
(0.642 g, 6.40 mmol), NaH (0.200 g, 8.32 mmol), BnBr (0.72 mL,
6.1 mmol), and 22 mL of dry THF for 12 h. Purification by flash
chromatography (95:5 hexanes/EtOAc) afforded 28 (0.730 g, 63%) as
a colorless oil: 1H NMR (500 MHz, CDCl3)
d
7.19–7.35 (m, 5H), 5.46 (q,
d
7.61 (d, J¼8.5, 2H), 7.47 (d, J¼8.6, 2H), 5.39–5.42 (m, 1H), 4.55 (s,
J¼6.0,1H), 4.44 (d, J¼11.9,1H), 4.24 (d, J¼11.9,1H), 3.86 (q, J¼6.5,1H),
2H), 4.02 (d, J¼6.9, 2H), 1.77 (s, 3H), 1.67 (s, 3H); 13C NMR (125 MHz,
1.66 (d, J¼6.5, 3H),1.62 (s, 3H),1.26(d, J¼6.5, 3H); 13CNMR (125 MHz,
CDCl3)
d
142.8, 137.8, 129.7 (q, J¼31), 127.7, 126.5 (q, J¼293), 125.3
CDCl3)
d
139.1, 136.6, 128.4, 127.8, 127.4, 122.0, 80.6, 69.6, 20.3, 13.2,
(q, J¼3.8),120.7, 71.2, 67.0, 25.9,18.1; IR (thin film) 2975, 2860,1420,
1326, 1066, 823 cmꢁ1; HRMS (ESI) m/z calcd for C13F3H15NaO
(MþNa)þ 267.0973, found 267.0977. Anal. Calcd for C13H15OF3: C,
63.93; H, 6.19. Found: C, 63.97; H, 6.22.
10.2; IR (thin film) 2977, 2861, 1454, 1204, 1093, 734 cmꢁ1; HRMS
(ESI) m/z calcd for C13H18NaO (MþNa)þ 213.1255, found 213.1255.
Anal. Calcd for C13H18O: C, 82.06; H, 9.53. Found: C, 81.62; H, 9.39.
4.1.5. Allylic silane 29
4.1.9. Allylic silane 40
The representative procedure for the synthesis of allylic silanes
was followed using allylic ether 28 (0.190 g, 1.00 mmol), silacyclo-
propane 10 (0.337 g, 1.50 mmol), CuOTf$PhMe (0.026 g,
0.050 mmol, 2:1 complex), and 6.7 mL of toluene for 12 h. Purifi-
cation by flash chromatography (99:1 hexanes/EtOAc) afforded an
inseparable 67:33 E/Z isomeric mixture of 29 (0.222 g, 67%) as
The representative procedure for the synthesis of allylic silanes
was followed using allylic ether 39 (0.244 g, 1.00 mmol), silacy-
clopropane 10 (0.337 g, 1.50 mmol), CuOTf$PhMe (0.026 g,
0.050 mmol, 2:1 complex), and 6.7 mL of toluene for 12 h. Purifi-
cation by flash chromatography (99:1 hexanes/EtOAc) afforded 40
(0.313 g, 81%) as a colorless oil: 1H NMR (500 MHz, CDCl3)
d 7.60 (d,
a colorless oil: 1H NMR (500 MHz, CDCl3)
d
7.24–7.35 (m, 12.5H),
J¼8.4, 2H), 7.46 (d, J¼8.5, 2H), 5.32–5.33 (m, 1H), 4.96 (s, 2H), 1.72
5.24–5.26 (m, 1.5H), 5.10–5.11 (m, 1H), 4.96–4.98 (m, 5H), 2.65–2.67
(m, 1H), 2.10–2.12 (1.5H), 1.81 (s, 3H), 1.67 (s, 4.5H), 1.62–1.63 (m,
3H), 1.56–1.58 (m, 4.5H), 1.31–1.33 (m, 4.5H), 1.26–1.28 (m, 3H), 1.12
(d, J¼8.2, 2H), 1.65 (s, 3H), 1.62 (s, 3H), 1.07 (s, 18H); 13C NMR
(125 MHz, CDCl3)
d
145.8, 129.2, 129.0 (q, J¼35), 125.8, 124.4 (q,
J¼249), 125.1 (q, J¼3.8), 120.1, 65.5, 28.3, 25.9, 21.6, 17.7, 12.2; IR
(thin film) 2933, 2859, 1325, 1127, 1067, 824 cmꢁ1; HRMS (ESI) m/z
calcd for C21F3H33NaOSi (MþNa)þ 409.2151, found 409.2155. Anal.
Calcd for C21H33OSiF3: C, 65.25; H, 8.60. Found: C, 65.52; H, 8.83.
(br s, 45H); 13C NMR (125 MHz, CDCl3)
d 141.8, 141.5, 140.1, 139.9,
128.14, 128.13, 126.63, 126.62, 125.61, 125.58, 117.7, 116.8, 66.0, 65.7,
30.6, 29.8, 29.2, 29.1, 28.8, 23.6, 23.3, 23.0, 22.9, 22.8, 22.5,18.0,16.4,
16.3, 13.4, 13.7; IR (thin film) 2966, 2858, 1473, 1376, 1113,
821 cmꢁ1; HRMS (APCI) m/z calcd for C21H36NaOSi (MþNa)þ
355.2433, found 355.2440. Anal. Calcd for C21H36OSi: C, 75.84; H,
10.91. Found: C, 76.08; H, 11.08.
4.1.10. Allylic ether 41
The representative procedure for the synthesis of aryl-protected
allylic alcohols was followed using 3-methyl-2-buten-1-ol
(0.50 mL, 5.00 mmol), p-methoxybenzyl chloride (0.68 mL,
5.00 mmol), NaH (0.360 g, 15.0 mmol), and 17 mL of THF for 12 h.
Purification by flash chromatography (95:5 hexanes/EtOAc) affor-
ded 41 (0.990 g, 96%) as a colorless oil: 1H NMR (500 MHz, CDCl3)
4.1.6. Benzylic silane 36
To a J. Young NMR tube were added benzaldehyde dimethyl
acetal (35) (19 mL, 0.125 mmol), silacyclopropane 10 (0.034 g,