References
<A NAME="RG07703ST-1">1</A>
IICT Communication No. 030201.
<A NAME="RG07703ST-2A">2a</A>
Greene TW.
Protective Groups in Organic Synthesis
Wiley;
New York:
1991.
<A NAME="RG07703ST-2B">2b</A>
Kocienski PJ.
Protecting Groups
Thieme;
Stuttgart, New York:
1994.
<A NAME="RG07703ST-2C">2c</A> For a recent review, see:
Jarowski K.
Kocienski PJ.
J. Chem. Soc., Perkin Trans. 1
2001,
2109
<A NAME="RG07703ST-3">3</A>
Guibe F.
Tetrahedron
1997,
53:
13509
<A NAME="RG07703ST-4">4</A>
Gigg R.
J. Chem. Soc., Perkin Trans. 1
1980,
738
<A NAME="RG07703ST-5">5</A>
Gigg R.
Warren CD.
J. Chem. Soc., Perkin Trans. 1
1968,
1903
<A NAME="RG07703ST-6">6</A>
Gent PA.
Gigg R.
Conant R.
J. Chem. Soc., Perkin Trans. 1
1973,
1858
<A NAME="RG07703ST-7A">7a</A>
Hubert AJ.
Reimlinger H.
Synthesis
1969,
97
<A NAME="RG07703ST-7B">7b</A>
Prosser T.
J. Am. Chem. Soc.
1961,
83:
1701
<A NAME="RG07703ST-7C">7c</A>
Pricc CC.
Snyder WH.
J. Am. Chem. Soc.
1961,
83:
1773
<A NAME="RG07703ST-8">8</A>
Tsuritani T.
Shinokubo H.
Oshima K.
Tetrahedron Lett.
1999,
40:
8121
<A NAME="RG07703ST-9">9</A>
Suresh Babu B.
Chinna Raju B.
Srinivas PV.
Madhusudana Rao J.
Tetrahedron Lett.
2003,
44:
2525
<A NAME="RG07703ST-10A">10a</A>
Vatele JM.
Synlett
2001,
1989
<A NAME="RG07703ST-10B">10b</A>
Vatele JM.
Synlett
2002,
507
<A NAME="RG07703ST-10C">10c</A>
Vatele JM.
Tetrahedron
2002,
58:
5689
<A NAME="RG07703ST-11">11</A>
Jungheim LN.
Tetrahedron Lett.
1989,
30:
1889
<A NAME="RG07703ST-12">12</A>
Yadav JS.
Subba Reddy BV.
Rao CV.
Chand PK.
Prasad AR.
Synlett
2002,
137
<A NAME="RG07703ST-13">13</A>
Nishizawa M.
Yamamoto H.
Seo K.
Imagawa H.
Sugihara T.
Org. Lett.
2002,
4:
1947
<A NAME="RG07703ST-14">14</A>
Sharma GVM.
Mahalingam AK.
Lavanya B.
Radha Krishna P.
Tetrahedron Lett.
2000,
41:
10323
<A NAME="RG07703ST-15">15</A>
Sharma GVM.
Ilangovan A.
Mahalingam AK.
J. Org. Chem.
1998,
63:
9103
<A NAME="RG07703ST-16">16</A>
Sharma GVM.
Ilangovan A.
Synlett
1999,
1963
<A NAME="RG07703ST-17">17</A>
General Experimental Procedure: A stirred solution of the prenyl ether/ester (1 mmol) in CH3CN (5 mL) was treated with ZrCl4 (0.046 g, 0.2 mmol), NaI (0.03 g, 0.2 mmol) and heated at reflux until complete consumption
of the starting material (TLC analysis). The solvent was removed under reduced pressure,
the residue dissolved in EtOAc (2 × 10 mL) and washed with H2O (2 × 10 mL) and brine (15 mL). The organic layer was dried (Na2SO4) and evaporated under reduced pressure to afford a crude product which on purification
by column chromatography (silica gel, 60-120, EtOAc-hexane, 5:95) furnished alcohol/acid.
Spectral data for selected compounds: Compound 4: IR (neat): 1510, 1745, 2362, 2858, 2936 cm-1. 1H NMR (200 MHz, CDCl3): δ = 1.36-1.43 (m, 8 H), 1.68 (s, 3 H), 1.71 (s, 3 H), 2.10 (s, 3 H), 3.57 (t, J = 6.5 Hz, 2 H), 3.88 (d, J = 4.7 Hz, 2 H), 4.05 (t, J = 6.4 Hz, 2 H), 5.29-5.32 (t, J = 6.5 Hz, 1 H). MS (EI): m/z (%) = 228 [M+]. Compound 8: IR (neat): 1376, 1510, 1620, 2932, 2986 cm-1. 1H NMR (200 MHz, CDCl3): δ = 1.38 (s, 6 H), 1.42 (s, 3 H), 1.52 (s, 3 H), 1.68 (s, 3 H), 1.73 (s, 3 H),
3.87 (d, J = 4.6 Hz, 2 H), 4.03 (ddd, J = 4.0, 6.6 Hz, 1 H), 4.25 (ddd, J = 4.0, 4.5 Hz, 2 H), 4.32 (dd, J = 2.5, 5.1 Hz, 1 H), 4.39 (dd, J = 1.5, 8.0 Hz, 1 H), 4.61 (dd, J = 2.5, 8.0 Hz, 1 H), 5.28-5.31 (t, J = 6.5 Hz, 1 H) 5.52 (d, J = 5.1 Hz, 1 H). MS (EI): m/z (%) = 328 [M+]. Compound 6a: IR(neat): 1260, 1510, 1590, 2920, 3515 cm-1. 1H NMR (200 MHz, CDCl3): δ = 1.36-1.64 (m, 8 H), 3.39-3.42 (t, J = 5.6 Hz, 2 H), 3.59-3.63 (t, J = 5.4 Hz, 2 H), 3.92 (d, J = 6.2 Hz, 2 H), 5.18-5.25 (m, 2 H) 5.84-5.86 (m, 1 H). MS (EI): m/z (%) = 158 [M+]. Compound 7a: IR (neat): 1226, 1523, 2862, 2958, 3506 cm-1. 1H NMR (200 MHz, CDCl3): δ = 1.36-1.61 (m, 8 H), 1.72 (d, J = 6.4 Hz, 3 H), 3.37 (t, J = 6.5 Hz, 2 H), 3.62 (t, J = 6.4 Hz, 2 H), 3.96 (d, J = 4.8 Hz, 2 H), 5.61 (m, 2 H). MS (EI): m/z (%) = 172 [M+]. Compound 15: IR (neat): 1220, 1345, 1565, 1745, 2885, 2930 cm-1. 1H NMR (200 MHz, CDCl3): δ = 0.94-1.20 (m, 6 H), 1.77 (s, 3 H), 1.82 (s, 3 H), 2.18 (m, 1 H), 4.31 (m, 1
H), 4.61 (d, J = 6.6 Hz, 2 H), 5.14 (s, 2 H), 5.32 (t, J = 6.4 Hz, 1 H) 7.39 (m, 5 H). MS (EI): m/z (%) = 319 [M+], 252 [M+ - 69]. Compound 16: IR (neat): 1225, 1350, 1545, 1750, 2865, 2935 cm-1. 1H NMR (200 MHz, CDCl3): δ = 1.22 (s, 9 H), 1.77 (s, 3 H), 1.81 (s, 3 H), 2.47 (t, J = 4.8 Hz, 2 H), 3.38 (t, J = 4.6 Hz, 2 H), 4.56 (d, J = 6.4 Hz, 2 H), 5.10 (br s, 1 H) 5.31 (t, J = 6.4 Hz, 1 H). MS (EI): m/z (%) = 258 [M+ + 1].