Electronic Supplementary Information for Stereoselective tricyclization of a dienyne by titanium aryloxide centers; Unprecedented ring expansion via insertion into a titanium-vinyl bond.

The reaction mixture is kept at –78o C and stirred for another 45 min, then quenched with saturated ammonium chloride solution.. The resulting brown suspension was filtered and the solve

Electronic Supplementary Information for

Stereoselective tricyclization of a dienyne by titanium aryloxide centers; Unprecedented ring expansion via insertion into a titanium-vinyl bond.

Richard A Himes,a Phillip E Fanwicka and Ian P Rothwell*a

a Department of Chemistry 1393 Brown Building, Purdue University, West Lafayette, IN 47907-1393, USA Fax: 765-494-0239; Tel: 765-494-5473; E-mail: rothwell@purdue.edu

Preparation of 6-Hepten-1-yne (1)

5-Bromo-1-pentene was prepared by heating 1,5-dibromopentane (100 g, 435 mmol) to 195oC (oil bath temperature) while adding HMPA (90 mL) dropwise The mixture is then heated at 220oC until product no longer distills The product is then redistilled (bp 126o C) to yield 37.2 g (57.5%) 1H NMR (CDCl3, 25oC): 5.65-5.85 (m, 1 H), 5.2-5.0 (m, 2 H), 3.2 (t, 2 H), 2.2 (q, 2 H), 1.95 (quin., 2 H) Bromopentene (37.41 g,

250 mmol) is added dropwise over one hour to a stirred slurry of lithium acteylide-ethylenediamine complex (34.37g, 375 mmol) in DMSO cooled to 00 C When addition complete, the mixture is allowed to warm to room temperature and stir for two hours The reaction is quenched with water and then distilled using a Dean-Stark trap until only water is collected The organic fraction is dried over molecular sieves then distilled (bp = 92-95o C) to yield 16.7 g (70.6%) 7 1H NMR (C6D6, 25o C): 5.59-5.45 (m, 1 H), 4.95-4.87 (m, 2 H), 1.93-1.88 (m, 2 H), 1.75 (t, 4J(1H-1H) = 2.7 Hz, 1 H), 1.36 (quin, 2 H); 13C NMR (C6D6): 138.20, 115.67, 84.38, 69.38, 33.20, 28.27, 18.28

Preparation of 1-Trimethylsilyl-6-hepten-1-yne (2).

nBuLi (21.3 mL, 53.2 mmol) is added dropwise to a THF solution of 6-hepten-1-yne (5.0 g, 53.2 mmol) at –78o C The mixture is stirred 45 min at this temperature 17.3

g chlorotrimethylsilane (159.6 mmol) is added dropwise The reaction mixture is kept at –78o C and stirred for another 45 min, then quenched with saturated ammonium chloride solution Product is extracted with diethyl ether, dried over MgSO4, and purified by

column chromatography eluted with pentane to yield 6.11 g (69.2%) 2 1H NMR (C6D6):

5.65-5.55 (m, 1 H), 5.0-4.85 (m, 2 H), 2.0-1.94 (m, 2 H), 1.4 (quin, 2H), 0.17 (s, 9 H);

13C (C6D6): 137.89, 115.28, 107.50, 84.81, 32.95, 28.06, 19.43, 0.30

Preparation of [Ti(OC6HPh4-2,3,5,6)2{C(Si(CH3)3)C(C3H6)CHCH2 }] (3).

Method A: To a stirred mixture of [Ti(OC6HPh4-2,3,5,6)2Cl2] (3.00g, 3.29 mmol)

and 1-trimethylsilyl-6-hepten-1-yne (2) (1.09 g, 6.06 mmol) in benzene (100 mL) was

slowly added BunLi (6.06 mmol) in hexanes (2.5M solution) The resulting brown suspension was filtered and the solvent removed under vacuum The crude residue was washed three times with hexane then recrystallized from a saturted benzene solution layered with pentane to afford 1.96 g (64.2%) of the title compound as a yellow powder

Method B: 1.00 g (1.06 mmol) of [Ti(OC6HPh4-2,3,5,6)2{CH2CH(C4H8)CHCH2}]

(8) was dissolved in 75 mL of benzene To this solution was added 2.0 equivalents of 1-trimethylsilyl-6-hepten-1-yne (8) (0.21 g, 1.26 mmol) The reaction is stirred overnight.

Solvent is removed en vacuo and the product recrystallized from a saturated benzene solution layered with pentane The title compound is isolated as 0.52 g (48.7%) of yellow powder Anal Calcd for TiC70H60SiO2: C, 83.31; H, 5.99 Found: C, 82.09; H, 6.08 1H NMR (C6D6):  7.4-6.8 (aromatics); 2.56 (dd, 1 H), 2.22-2.16 (m, 1 H), 2.1 (b, 2 H), 1.92-1.82 (m, 1 H), 1.4 (b, 1 H), 1.06 (dd, 1 H), 0.8 (b, 1 H), -0.13 (s, 9 H), -0.59 (t, J

= 10.8 Hz, 1 H) 13C NMR (CD2Cl2):  215.70 (TiCSiMe3); 164.80; 160.05, 160.73

(Ti-O-C); 76.07 (TiCH2), 40.95, 38.85, 27.88, 19.96, 0.56

Preparation of 1,11-Dodecadien-6-yne (4).

nBuLi (17.49 mL, 43.72 mmol) is added dropwise to a THF solution of 6-hepten-1-yne (4.11 g, 43.72 mmol) at –78o C The mixture is stirred 45 min at this temperature 6.51 g 5-bromo-1-pentene (43.72 mmol) in HMPA is added dropwise The reaction mixture is kept at –78o C and stirred for another 45 min, then slowly allowed to warm to room temperature and stirred overnight The reaction is quenched with water Product is extracted with diethyl ether, dried over MgSO4, and purified by column chromatography

eluted with pentane to yield 2.82 g (39.8%) 4 1H NMR (C6D6): 5.73-5.60 (m, 2 H),

5.02-4.91 (m, 4 H), 2.08-2.01 (m, 4 H), 1.46 (quin, 4 H); 13C (CDCl3): 138.24, 115.14, 80.25, 33.04, 28.57, 18.51 HRMS calcd for C12H17 [M-H]: 161.1330, found: 161.1325

Preparation of meso-[Ti(OC6H3Ph2-2,6)2{CH2CH(C3H6)CC(C3H6)CHCH2}] (5a)

A red benzene solution (100 mL) of 2.0 g (3.26 mmol) [Ti(OC6H3Ph2-2,6)2Cl2]

and 1.23 g (7.59 mmol) 1,11-dodecadien-6-yne (4) is stirred over an amalgam of sodium

(0.16 g, 6.95 mmol) in mercury The solution changes color to purple and eventually to dark brown during overnight stirring The solution is decanted from the mercury and salts and filtered through celite The solvent is removed en vacuo and the orange-yellow solid is recrystallized from hot benzene to afford 1.54 g (67.4%) of the title compound as

a orange crystals The crude compound may be slowly crystallized from a hot benzene solution to yield X-ray quality crystals 1H NMR (C6D6): 7.47-6.89 (aromatics), 2.84 (dd, 2 H), 2.01-1.85 (m, 4H), 1.58 (t, J = 12 Hz, 2H), 1.50-1.31 (m, 6H), 1.29-1.21 (m, 4H), 0.86-0.82 (m, 4H), -0.062 (d, J = 10.5 Hz, 2H); 13C NMR (C6D6): 160.23, 159.78

(Ti-O-C); 137.17, 103.13 (TiCH2), 43.52, 38.71, 31.90, 24.52 Anal Calcd for TiC49H44O2: C, 82.58; H, 6.18 Found: C, 82.05; H, 6.42

Preparation of meso-[Ti(OC6HPh4-2,3,5,6)2{CH2CH(C3H6)CC(C3H6)CHCH2}] (5b)

Method A: To a stirred mixture of [Ti(OC6HPh4-2,3,5,6)2Cl2] (3.00 g, 3.29

mmol) and 1,11-dodecadien-6-yne (4) (0.69 g, 4.27 mmol) in benzene (100 mL) was

slowly added BunLi (6.91 mmol) in hexanes (2.5M solution) The resulting brown suspension was filtered and the solvent removed under vacuum The crude residue was washed three times with hexane to afford 1.77 g (53.6%) of the title compound as a brown-yellow powder

Method B: A sample of [Ti(OC6HPh4-2,3,5,6)2{CH2CH(C4H8)CHCH2}] (8) was

placed in a sealed NMR tube and dissolved in d6-benzene To this was added one drop of

1,11-dodecadien-6-yne (4) The solution is heated at 100oC for approximately 30 min The solution is layered with pentane to afford the title compound as yellow microcrystals

1H NMR (C6D6): 7.39-6.85 (aromatics), 2.85 (dd, 2 H), 2.06-1.82 (m, 4H), 1.50 (t, 2H), 1.46-1.32 (m, 6H), 1.22 (m, 4H), 0.87 (m, 4H), -0.47 (d, J = 10.8 Hz, 2H); 13C NMR

(C6D6): 160.77 (Ti-O-C; 2 nearly overlapping peaks), 142.46, 104.64 (TiCH2), 43.76, 38.83, 32.02, 24.51 Anal Calcd for TiC72H60O2: C, 85.71; H, 5.98 Found: C, 82.16;

H, 5.92

Preparation of (2-Methylcyclopentylidene)-2-methylcyclopentane (6)

A sample of [Ti(OC6H3Ph2-2,6)2{CH2CH(C3H6)CC(C3H6)CHCH2}] (5a) was

placed in a sealed NMR tube and dissolved in d6-benzene The solution was exposed to

ambient atmosphere After hydrolysis was complete, the title organic product 6 was

isolated by thin-layer chromatography eluted with pentane and extracted with

dichloromethane After removal of solvent, 6 was isolated as a colorless liquid 1H NMR (C6D6): 2.67-2.63 (m, 2 H), 2.14-2.10 (m, 4 H), 1.74-1.57 (m), 1.39-1.35 (m), 1.06 (d, J = 6.9 Hz, 6 H), 0.92-0.89 (m) HRMS calcd for C12H20: 164.1565 Found: 164.1558

1H-1H COSY NMR experiment for [meso-Ti(OC6H3-Ph2 -2,6)2{CH2CH(C3H6)CC(C3H6)CHCH2}]