Custom Column Help: Literal expected

Hi all,

I'm trying to create a custom column but I can't seem to get the formula right. I get the message literal value expected.

Any idea where I'm going wrong? 

if ([Column] >= 6.1 && [Column] <= 7.0) then “Value1"
else if [Column] >= 4.78 and [Column] <= 4.99 
then “Value2”
else if [Column] >= 3.21 and [Column] <= 3.5
then “Value3”
else if [Column] >= 1.4 and [Column] <= 3.20
then “Value4”
else “”