R
SYNTHETIC COMMUNICATIONSV
5
2 -Isopropyl-4-(5-(2-(4-methoxybenzyloxy)propyl)furan-3-yl)-butan-1-ol (2)
To a solution of 12 (1.3 g, 2.2 mmol) in THF (40 mL), was added TBAF (1.0 M in THF,
2.64 mL, 2.64 mmol) and stirred for 1.5 h. The reaction mixture was quenched with aq.
NH4Cl solution (20 mL), extracted with EtOAc (3 ꢂ 10 mL). Solvent was evaporated
under reduced pressure and purified by SiO2 column (EtOAc:hexane = 1:9) to give 2
(836 mg, 88%) colorless oil (Rf = 0.5, 2:1 ¼ hexanes:ethyl acetate). IR (neat): 3435, 2958,
1
2876, 1723, 1514, 1461, 1249, 971, 825 cmꢀ1. H NMR (CDCl3, 400 MHz): d 7.21 (d,
J ¼ 8.5 Hz, 2H), 7.09 (s, 1H), 6.85 (d, J ¼ 8.6 Hz, 2H), 5.96 (s, 1H), 4.44 (q, J ¼ 11.4 Hz,
2H), 3.83–3.73 (m, 4H), 3.67–3.55 (m, 2H), 2.89 (dd, J ¼ 14.9, 6.1 Hz, 1H), 2.68 (dd,
J ¼ 14.9, 6.6 Hz, 1H), 2.51–2.31 (m, 2H), 1.84 (tt, J ¼ 13.6, 6.9 Hz, 1H), 1.65–1.45 (m,
3H), 1.41–1.32 (m, 1H), 1.20 (d, J ¼ 6.1 Hz, 3H), 0.90 (dd, J ¼ 6.9, 1.5 Hz, 6H). 13C
NMR (CDCl3, 100 MHz): d 159.1, 153.2, 137.1, 130.9, 129.2, 128.7, 126.1, 113.9, 113.8,
108.2, 77.4, 77.0, 76.7, 73.5, 70.3, 63.6, 55.3, 46.1, 35.5, 28.2, 27.9, 23.3, 19.9, 19.8, 19.3.
MS (ESI): m/z 383 (M þ Na)þ. HRMS (ESI): m/z calcd for C22H32O4Na (M þ Na)þ:
383.2198, found: 383.2202.
Funding
CRR thanks the Council of Scientific and Industrial Research (CSIR), New Delhi for financial
support as part of XII-five year plan project under title ORIGIN (CSC-108). YLP thanks
Department of Science and Technology (DST), Ministry of Science and Technology for financial
grant under Women Scientists Scheme-A (WOS-A), Grant No. SR/WOS-A/CS-108/2017 (G).
SZM and GK thank the Council of Scientific and Industrial Research (CSIR), New Delhi for
research fellowship [Communication No. IICT/Pubs./2019/074].
References
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