The development and evaluation of a continuous flow process for the lipase- mediated oxidation of alkenes

• Charlotte Wiles,
• Marcus J. Hammond and
• Paul Watts

Beilstein J. Org. Chem. 2009, 5, No. 27, doi:10.3762/bjoc.5.27

• ), 97 (77), 85 (15), 95 (100), 83 (15), 69 (15) and 55 (25); GC-MS tR = 5.26 min. The spectroscopic data obtained for 1-methylcyclohexene oxide (7) was consistent with that reported within the literature [36]. 1,2-Epoxy-1-phenylethane (styrene oxide) A pre-mixed solution containing styrene (9, 0.1 M

• -epoxy-1-phenylethane as a colourless oil (0.086 g, 99.2% yield); 1H NMR (400 MHz, CDCl3) δ 2.75 (dd, J = 2.8, 5.6, 1H), 3.08 (dd, J = 4.1, 5.6, 1H), 3.80 (dd, J = 2.8, 4.1, 1H) and 7.24–7.33 (m, 5H); 13C NMR (100 MHz, CDCl3) δ 51.0 (CH2), 51.1 (CH), 125.3 (2 × CH), 128.0 (CH), 128.2 (2 × CH) and 137.5

• (C); m/z (EI) 121 (M++1, 5%), 120 (20), 119 (50), 92 (25), 91 (100), 89 (40) and 77 (20); GC-MS tR = 5.37 min. The spectroscopic data obtained for 1,2-epoxy-1-phenylethane was consistent with that reported within the literature [37]. cis-1,2-Diphenyloxirane (cis-stilbene oxide, 13) A solution

A short stereoselective synthesis of (+)-(6R,2′S)-cryptocaryalactone via ring- closing metathesis

• Palakodety Radha Krishna,
• Krishnarao Lopinti and
• K. L. N. Reddy

Beilstein J. Org. Chem. 2009, 5, No. 14, doi:10.3762/bjoc.5.14

• alcohol that was obtained from a regioselective ring-opening reaction of 2,3-epoxy alcohol 8. The known 2,3-epoxy alcohol 8 was synthesized from the corresponding dienyl alcohol by the well-established Sharpless asymmetric epoxidation conditions in >94% ee as described in literature [38][39]. Compound 8

• wherein a chiral 2,3-epoxy alcohol was the starting material and Sharpless asymmetric epoxidation and Carreira asymmetric alkynylation were used as key steps for generating unambiguous assigned stereocenters. More importantly, the Grubbs’ ring-closing metathesis protocol was applied to construct the final

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

• absolute configuration of natural-8 at C-8 to R (Scheme 3). In their synthesis, asymmetric epoxidation of 19 directed by L-(+)-diisopropyl tartrate gave epoxy alcohol 20; the THF ring of 21 was then constructed under CSA catalyzed one-pot transformation. After deprotection of the isopropylidene acetal of

• ,19S,20S)-cis-murisolin (112), and (15R,16R,19R,20S)-murisolin A (121) (Scheme 18). The mono-THF moieties were synthesized from epoxy alcohol 122 by using Sharpless AD-mix-β for the threo-trans-threo THF moiety 123, a AD-mix-β followed by the Mitsunobu reaction for the erythro-cis-threo THF moiety 125

Diels- Alder reactions using 4,7-dioxygenated indanones as dienophiles for regioselective construction of oxygenated 2,3-dihydrobenz[f]indenone skeleton

• Natsuno Etomi,
• Takuya Kumamoto,
• Waka Nakanishi and
• Tsutomu Ishikawa

Beilstein J. Org. Chem. 2008, 4, No. 15, doi:10.3762/bjoc.4.15

• and [4.4.3]propellane. The addition of Lewis acid did not affect the product ratio, whereas the use of the 6-bromoindanetrione exclusively afforded the latter propellane. On the other hand, DAR of benzyne derived from bromoindan and furan gave 5,8-epoxy-2,3-dihydrobenz[f]indene, which was subjected to

• B; quinone route) [28]; 2) regioselective ring-opening of 5,8-epoxy-2,3-dihydrobenz[f]indenone 11 derived from benzyne 10 and furan (9) (path C, benzyne route). Now we report that both of the methods are effective for the construction of the 2,3-dihydrobenz[f]indenone skeleton, but not for the

• examined by treatment of bromoindanone acetal 25, prepared from bromoindanone 18, with a base in the presence of furan (9) (Scheme 3). Application of Giles' protocol [41] using sodium amide as a base in the presence of a large excess amount (ca. 15 equivalents) of furan (9) in THF gave 5,8-epoxy-2,3