Create an data.frame in R with dynamically assigned column names

Question

I need to create a data.frame that will be populated one row at a time by results of a for loop. It has 45 columns: the names of five of these are static but the remainder are read in (as a vector) from an external CSV file at run time. I'm looking for something along the lines of

goalsMenu <- read.csv("Phase 1 goalsmenu.csv", header = TRUE)
colHeads <- c("analysis","patient","date",as.vector(goalsMenu$Name),"CR")
output <- data.frame(colHeads)

however this creates a one-column data.frame with column name of colHeads.

colHeads <- list("analysis","patient","date",as.vector(goalsMenu$Name),"CR")

seems a step in the right direction but I need to "flatten" it to create the desired data.frame structure

could you advise please?