Question

Give the structure of the organic product expected when i2ch2 reacts with each of the following alkenes in the presence of a zn–cu couple:

Answer 1

(Z)-3-methyl-2-pentene H2C H2 C CH3 CH3

Answer 2

The given reagent Zn/Cu, CH2I2 form a free intermediate radical. Zn/Cu + CH,I, → İZnCH,I This intermediate free radical attack on the carbon atom of double bond present in reactants and forms a cyclopropane. This reaction is known as Simmons-smith reaction. The reaction for (Z)-3-methyl-2-pentene is shown below CH3 CH2 CH3 ZnlCu 1H3C CH212 H,C CH3 CH3 Znl2 H,C Hence, the correct wedge and dash bonds figure is given below (1S,2R)-1-ethyl-1,2-dimethylcyclopropane

The reaction is shown below CH ZnCu CH-CH, - CH-CH CH2L CH, Znl, + CH-CH

Answer 3

CH2 Но