Question

Given that alpha hydrogens can be substituted with halogens, substitution with what halogen is not covered in the text?

Select one:

a. bromine

b. iodine

c. fluorine

d. chlorine

Question 2

Alpha alkylation of ketones using LDA is done under which conditions?

Select one:

a. acidic

b. neutral

c. basic

Question 3

Alpha alkylations using LDA as a reagent is which type of reaction?

Select one:

a. Electrophilic Addition

b. SN2

c. E1

d. SN1

e. Electrophilic Aromatic Substitution

f. E2

Question 4

Alpha alkylation when using LDA and a simple ketone is limited to which type of alkyl halide?

Select one:

a. tertiary

b. primary

c. secondary

Question 5

Alpha alkylation of dicarbonyl compounds cannot be done with which type of alkyl halide?

Select one:

a. primary

b. secondary

c. tertiary

Question 6

A type of drug that can be synthesized by alkylation of dicarbonyl compounds is?

Select one:

a. barbiturates

b. opiates

c. steroids

d. amphetamines

Answer 1

1. Free radical substitution of haloalkanes is more facile for chlorine and less for iodine.

2.Alpha alkylation of ketones using LDA is done under which conditions?

b. neutral condition (only basic LDA not other bases)

The LDA is strong base and forms lithium enolate which reacts with alkyl halides, gives alkylated product.

in acidic condition it will form enol and in base it forms enolate ( if these conditions used selectivity will be reversed)

3.Alpha alkylations using LDA as a reagent is which type of reaction?

SN2 REACTION. ( KINETIC ENOLATE), LESS SUBSTITUTED ELECTROPHILES

LDA FORMS Enolate and which is more nucleophilic which reacts with SN2 reactive electrophiles.

4.Alpha alkylation when using LDA and a simple ketone is limited to which type of alkyl halide?

Tertiary, because enolate is more nucleophilic and IT IS KINETIC ENOLATE always reacts with SN2 REACTIVE Electrophiles( LESS SUBSTITUTED), primary but reactive like allyl halides etc.

5. Alpha alkylation of dicarbonyl compounds cannot be done with which type of alkyl halide?

tertiary,

6.A type of drug that can be synthesized by alkylation of dicarbonyl compounds is?

steroids can be synthesised by alkylation of dicarbonyl compounds.