Reaction #56362

Reaction equation

1-ethoxy-1,3-pentadiene

butyl glyoxylate

1-ethoxy-1,3-pentadiene

butyl glyoxylate

hydroquinone

→

butyl-3-methyl-6-ethoxy-3,6-dihydro-2H-pyran-2-carboxylate

Solvents

methylene chloride

Conditions

Workup

1. 1
   Otherto give 28.0 g
2. 2
   OtherYield

Procedure

Following the procedure of Example 12, a solution of 26.7 g. (0.226 mol) of 1-ethoxy-1,3-pentadiene (purity, 95%), 32.5 g. (0.25 mol) of butyl glyoxylate and 0.250 g. of hydroquinone in 250 ml. of methylene chloride was refluxed for 48 hours to give 28.0 g. of a mixture of 1-ethoxy-1,3-pentadiene and butyl glyoxylate and 20.32 g. of distilled 2H-pyran butyl ester (b1.0 =100°-110°) as an oil. Yield based on 1-ethoxy-1,3-pentadiene, 34%.

Source