A new synthesis of 2,10,11-trioxatricyclo[4.4.4.0^1,6]tetradecane

Abstract

NORMAXD BEALJLIEU and PIERRE DESLONGCHAMPS. Can. J. Chem. 58.875 (1980). A simple and convenient synthesis of tricyclic orthoester 1 (2.10.1l-trioxatricycl0[4.4.4~O~~~]tetradecane) is described.NORMAND BEAULIEU et PIERRE DESLOKGCHAI\.IPS. Can. J. Chem. 58, 875 (1980). to report a new synthesis of tricyclic orthoester 1 in which there is improvement on the number of steps. reaction conditions. ease of product isola-(RO-CH2-CH2-CH2),C-COOCH, tion. and overall yield. R = HEthyl his-ally1 acetate 2, which can be conve-10 R = CH,CO niently prepared by alkylation of diethyl malonate (5) with ally1 bromide followed by decarboxylation (NaCl in DMSO-H,O, (6)), was used as starting material.Ethyl bis-ally1 acetate 2 was alkylated (LDA, CH,==CH--CH2-Br, HMPT. -78"C, (7)) to give ethyl tri-ally1 acetate 3 (290% yield). Basic hydrolysis of 3 (KOH, C2H,0H, reflux, 15 days),6 up P gave the corresponding carboxylic acid 4 (95% yield) which was converted into the known (4) CH30H3 room temperature, 30 min? followed by tribr~mocarbo~ylic acid 5 (290% yield) by the the addition of excess acid (HcI. 2 N) gave crude photochemically induced addition of hydrogen diol lactone 8 which yielded tricyclic orthoester 1 bromide (hv, pentane, (8)). Treatment of tribromo-(88%) upon reflux in benzene. The tricyclic orcarboxylic acid 5 with triethylamine in thoester 1 was also obtained (66%) by treatment of dichloromethane furnished the expected dj-diacetate lactone 7 under acidic conditions 2.4 N bromoIactone 4 (290% yield) which was further HCl-(1: 11, room temperature, 2 h) followed transformed (CH,COONa. HMPT, room temper-by the addition of benzene and distillation. ature. 2 h , (9)) into the diacetate lactone 7 (50% Diacetaee lactone ' 9 was also hydrolysed with yield).triethylamine in methanol (4 days, room temperaBasic hydrolysis of &acetate lactone 7 (K,CO,, ture, (10)) to yield crude triol methyl ester 9 which was characterized spectroscopicaliy and by its 'Holder of a Natural Sciences and Englneenng ~~~~~~~h conversion into triacetate methyl ester 18. Treat- For personal use only.

Facile one-step synthesis of bis(NHC) ruthenium benzylidene catalyst for ring-closing metathesis

“…High resolution mass spectra were recorded with a Q-TOF mass spectrometry (Micromass, England) equipped with Z-spray ionization source. Diethyl diallylmalonate [10] and diallylmalononitrile [11] were prepared according to literature procedures. Methylene chloride was dried over CaH 2 , distilled and stored under nitrogen.…”

Catalytic Deallylation of Allyl‐ and Diallylmalonates.

“…Diethyl butylmalonate (5.4 g, 25 mmol), Na (0.58 g, 25 mmol), methallyl chloride (2.26 g, 25 mmol) and ethanol (30 mL). Yield 4.8 g (71 %) of a colourless liquid: 1 H NMR (CDCl 3 , Me 4 Si) δ 0.89 (t, J = 7.3 Hz, 3H), 1.11-1.19 (m, 2H), 1.25 (t, J = 7.1 Hz, 6H), 1.26-1.35 (m, 2H), 1.66 (bs, 3H), 1.84-1.91 (m, 2H), 2.67 (d, J = 0.9 Hz, 2H), 4.13-4.22 (m, 4H), 4.71-4.73 (m, 1H), 4.83.4.86 (m, 1H); 13…”

“…Diethyl butylmalonate (1.08 g, 5 mmol), Na (0.12 mg, 5 mmol), cinnamyl bromide (0.98 g, 5 mmol) and ethanol (6 mL). Yield 1.1 g (67 %) of a yellowish liquid: 1 H NMR (CDCl 3 , Me 4 Si) δ 0.89 (t, J = 7.3 Hz, 3H), 1.16-1.28 S-2 (m, 2H), 1.23 (t, J = 7.0 Hz, 6H), 1.28-1.36 (m, 2H), 1.88-1.96 (m, 2H), 2.79 (dd, J = 7.4, 1.2 Hz, 2H), 4.19 (q, J = 7.0 Hz, 4H), 6.04 (dt, J = 15.7, 7.5 Hz, 1H), 6.43 (d, J = 15.7 Hz, 1H), 7.18-7.40 (m, 5H); 13…”

“…1 H NMR yield 92 %. 1 H NMR (CDCl 3 , Me 4 Si) δ 0.90 (t, J = 7.2 Hz, 3H), 1.27 (t, J = 7.1 Hz, 6H), 1.28-1.38 (m, 4H), 1.84-1.96 (m, 2H), 3.01 (t, J = 7.5 Hz, 1H), 4.14-4.25 (m, 4H). The spectral characteristics of 2b were in agreement with the commercially available sample of the title compound (Aldrich).…”

“…1 H NMR yield 98 %. 1 H NMR (CDCl 3 , Me 4 Si) δ 1.26 (t, J = 7.0 Hz, 6H), 1.63 (dm, J = 6.2 Hz, 3H), 2.54-2.62 (m, 2H), 3.36 (t, J = 7.6 Hz, 1H), 4.14-4.24 (m, 4H), 5.32-5.44 (m, 1H), 5.49-5.60 (m, 1H). The spectral characteristics of 2h were in agreement with the previously published data.…”