I want to names dataframe's columns using a vector

I want to name dataframe’s columns using a vector of character. I don’t know why with the following code I get the error:

Error in names(x) <- value :
‘names’ attribute [5] must be the same length as the vector [1]

vec <- 1:5
vec <- as.data.frame(vec)
colnames(vec) <- c("a", "b", "c", "d", "e")

Thanks in advance

>Solution :

The as.data.frame still returns a single column. Instead, we may need to use as.data.frame.list

vec <- 1:5
vec <- as.data.frame.list(vec)
colnames(vec) <- c("a", "b", "c", "d", "e")

-output

> vec
  a b c d e
1 1 2 3 4 5