ethyl 8-forMyl-1,4-dioxaspiro[4.5]decane-8-carboxylate

Step 2: Preparation of ethyl 8-formyl-l, 4-dioxaspiro[4.5]decane-8-carboxylate. To a -78 °C solution of ethyl l, 4-dioxaspiro[4.5]decane-8-carboxylate (32.31 g, 151 mmol) in THF (250 mL) was added a solution of 2M lithium diisopropylamide (98 mL, 196 mmol) in THF via a cannula over 5 mins. The resulting brown solution was stirred at -78 °C. After lh, the cold bath was replaced with an ice bath and the reaction mixture was stirred at 0 °C for lh. The reaction mixture was again chilled to -78 °C and treated with a solution of ethyl formate (18.65 mL, 226 mmol) in THF (40 mL) added dropwise over 45 min. The resulting light brown reaction mixture was stirred at -78 °C for lh. The cold bath was removed and to the mixture was added dropwise saturated aqueous NHTo a -78 °C solution of ethyl 1, 4-dioxaspiro[4.5]decane-8-carboxylate (32.31 g, 151 mmol) in THF (250 mL) was added a solution of 2M lithium diisopropylamide (98 mL, 196 mmol) in THF via a cannula over 5 mins. The resulting brown solution was stirred at -78 °C. After 1h, the cold bath was replaced with an ice bath and the reaction mixture was stirred at 0 °C for 1h. The reaction mixture was again chilled to -78 °C and treated with a solution of ethyl formate (18.65 mL, 226 mmol) in THF (40mL) added dropwise over 45 min. The resulting light brown reaction mixture was stirred at -78 °C for 1h. The cold bath was removed and to the mixture was added dropwise saturated aqueous NHTo a solution of ethyl 1, 4-dioxaspiro[4.5jdecane-8-carboxylate (21 g, 98 mmol) in THF(150 mL) at -78 °C was added 2M LDA (64 mL, 127 mmol) dropwise. The resultingsolution was stirred at -78 °C for 1 h, then in an ice bath for 1.5 h. The reaction mixturewas chilled back to -78 °C and molecular sieves were added. Dried ethyl formate (12 mL, 147 mmol) was added dropwise slowly over 1 h. The reaction mixture was stirred at -78°C for 1 h. The cold bath was removed and the reaction was quenched with a saturatedsolution of NH4C1 in 0.5 N HC1 (250 mL) dropwise. The mixture was extracted with EtOAc (3 x 200 mL). The combined organic layer was washed with saturated solution of NH4C1 in 0.5 N HC1 (200 mL), brine (200 mL), dried over Na2SO4, and concentrated in vacuo. The cmde product was purified by silica gel column eluted with 0-20 percent ethyl acetate I hexanes to give the desired product as an oil (9.3 g, 39 percent). ‘H NMR (400MHz, CHLOROFORM-d) ö 9.54 (s, 1H), 4.21 (q, J=7.1 Hz, 2H), 3.98 - 3.90 (m, 4H), 2.25 -2.16 (m, 2H), 2.10 - 2.01 (m, 2H), 1.74 - 1.60 (m, 4H), 1.27 (t, J=7.2 Hz, 3H).

Molecular Weight:242.27
XLogP3:0.6
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:4
Exact Mass:242.11542367
Monoisotopic Mass:242.11542367
Topological Polar Surface Area:61.8
Heavy Atom Count:17
Complexity:296
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes