Question

Problem #1 Draw the major product(s) expected from the following sequence of reactions: A Br 1. t-BUOK 2. 03 ? 3. DMS Problem #2 Complete the following reactions: - CH₂ | NaP, NH40 , Na', NH3(0) H2(g) нс Hy() Pd on Cacog PbO2

Answer 1

1) The reaction with potassium tert-butoxide is an elimination, in which the less-substituted possible alkene is produced:

The followgin reaction with ozone breaks the double bond and the addition of DMS yields carbonyl groups on the carbons that participated in the double bond. In this case, the product would be:

2) These are 3 types of reduction of multiple bonds. Reduction with excess H₂ gas and a catalyst such as platinum yield the alkene, even if we start with an alkyne. The product would be:

The reaction with NH₃ and Na is a partial reduction which converts alkynes selectively to trans alkenes, so the product would be:

Finally, the reaction with H₂ on a "poisoned" catalyst, such as Pd on CaCO₃ and PbO₂, allows for the reduction of alkynes selectively to cis alkenes. The product in this case is: