n <- 1000
toydata <- data.frame(
  sex = as.character(ifelse(rnorm(n)>0, "M", "F")),
  value = rnorm(n)
)

p <- c(.1, .25, .5, .75, .9)

toydata %>%
  group_by(sex) %>%
  nest() %>%
  mutate(
    quantiles = map(data, ~quantile(.$value, p, na.rm=TRUE))
  )


# A tibble: 2 x 3
  sex   data               quantiles
  <fct> <list>             <list>
1 F     <tibble [491 × 1]> <dbl [5]>
2 M     <tibble [509 × 1]> <dbl [5]>