Method (b). A solution of 7 (100 mg, 0.354 mmol) in CH CN (1 mL) was treated with Sc(OTf) (180 mg,
3
3
0
.366 mmol), stirred at 18-20°C for 2 h, diluted with ether (10 mL), washed with water (5 × 1 mL), and dried. Solvent was
distilled off in vacuo to give a product (88 mg) that was chromatographed over a silica-gel column (1.8 g) as described in
Method (a) to give 12 (11 mg, 15%) and the mixture of acetates (4-6, 57 mg, 61%) in a 75.5:15.5:9 ratio.
Method (c). A solution of 7 (100 mg, 0.354 mmol) in CH CN (1 mL) was cooled in an ice bath, stirred, treated with
3
CF SO SiMe (0.07 mL, 86 mg, 0.387 mmol), stirred another 15 min at 0°C and 20 min at 18-20°C, and treated with water
3
3
3
(
5 mL) and ether (15 mL). The ether layer was separated, washed with NaHCO solution (3 × 2 mL) and water (3 × 2 mL),
3
and dried. Solvent was distilled off in vacuo to afford a product (86 mg) that was chromatographed over a silica-gel column
(1.8 g) as described for Method (a) to give 12 (12 mg, 16%) and the mixture of acetates (4-6, 62 mg, 66%) in a 90:9:1 ratio.
Method (d). A solution of PCl (140 mg, 0.672 mmol) in absolute ether (3 mL) was stirred, cooled in an ice bath,
5
treated with 7 (99 mg, 0.350 mmol) in absolute ether (2 mL), stirred for 3 h, treated dropwise with water (5 mL), diluted with
ether (10 mL), and transferred to a separatory funnel. The aqueous layer was separated. The ether layer was washed with
NaHCO solution (3 × 3 mL) and water (3 × 3 mL) and dried. The ether was distilled off in vacuo. Chromatography of the
3
resulting product (94 mg) over silica gel (1.88 g) as described for Method (a) produced 12 (2 mg, 3%) and the mixture of
acetates (4-6, 69 mg, 74%) in a 28:20:52 ratio.
Method (e). A solution of PCl (375 mg, 1.8 mmol) in drypyridine (2.5 mL) was stirred, cooled in an ice bath, treated
5
with 7 (100 mg, 0.354 mmol) in pyridine (2.5 mL), stirred another 6 h, treated dropwise with cooling and stirring with H SO
2
4
(
10%, 15 mL), and extracted with ether (3 × 10 mL). The extract was washed with H SO (10%, 3 mL), water (3 mL), NaHCO
2
4
3
solution (3 × 5 mL), and water (3 × 5 mL) and dried. Solvent was distilled in vacuo to afford a product (83 mg) that was
chromatographed over a silica-gel column (1.68 g) as described for Method (a) to isolate 12 (2 mg, 2%) and the mixture of
acetates (4-6, 71 mg, 76%) in a 28:49:23 ratio.
Method (f). A solution of 7 (108 mg, 0.382 mmol) in CH Cl (5 mL) was treated with Amberlist-15 (111 mg), stirred
2
2
at 18-20°C for 1 h 45 min, filtered, and washed with CH Cl (5 mL). The filtrate was evaporated to afford a product (98 mg)
2
2
that was chromatographed over a silica-gel column (2 g) as described for Method (a) to afford 12 (11 mg, 14%) and the mixture
of acetates (4-6, 73 mg, 72%) in a 63:21:16 ratio.
Preparation of a Mixture of Acetates (Drimenol, 4; Albicanol, 5; Isodrimenol, 6) from Drimandiol Diacetate (8).
Method (a). A solution of 8 (100 mg, 0.308 mmol) in hexane (5 mL) was treated with Merck silica gel (1 g) and boiled with
stirring for 3 h. The silica gel was filtered off and washed with hexane (5 mL) and separately with ether (10 mL). The hexane
filtrate was evaporated to afford 12 (10 mg). The ether filtrate was also evaporated. The resulting residue (65 mg) was
chromatographed over a silica-gel column (1.3 g) with elution byhexane to give an additional portion of 12 (2 mg). Total yield
1
2 mg (19%). Hexane:ether (49:1) eluted the mixture of acetates (4-6, 61 mg, 75%) in a 56:39:5 ratio.
Method (b). A solution of 8 (100 mg, 0.308 mmol) in DMSO (5 mL) was treated with NaHCO (36 mg, 4.28 mmol),
3
heated with stirring at 140-160°C for 10 h, cooled, diluted with water (50 mL), and extracted with ether (3 × 20 mL). The ether
extract was washed with water (2 × 10 mL) and dried. The ether was distilled off. The residue (73 mg) was chromatographed
over a silica-gel column (1.5 g) as described for Method (a) to afford 12 (3 mg, 4%) and the mixture of acetates (4-6, 63 mg,
7
7%) in a 25:53:22 ratio.
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