Read about a proxy variable in a .npmrc file but it does not work. Trying to avoid manually downloading all require packages and installing.
.npmrc
Use below command at cmd or GIT Bash or other prompt
$ npm config set proxy "http://192.168.1.101:4128"
$ npm config set https-proxy "http://192.168.1.101:4128"
where 192.168.1.101 is proxy ip and 4128 is port. change according to your proxy settings. its works for me.