how to redirect a specific loopback port to another address

I would like to redirect the postgres' port to another address which is running postgres. The postgres' instance is hosted on a virtualbox machine with host-only networking configuration. Unfortunately the following rule does not seem to make the job

echo "rdr pass inet proto tcp from any to 127.0.0.1 port 5432 -> 

172.16.0.2 port 5432" | sudo pfctl -ef -
pfctl: Use of -f option, could result in flushing of rules
present in the main ruleset added by the system at startup.
See /etc/pf.conf for further details.

No ALTQ support in kernel
ALTQ related functions disabled
pfctl: pf already enabled

$ psql -h 127.0.0.1 -p 5432 -U em3local
psql: could not connect to server: Network is unreachable

what's wrong with it?

Of course if I try to connect to 172.16.0.2 I can reach it correctly:

$psql -h 172.16.0.2 -p 5432 -U em3local
Password for user em3local: 

These are my current interfaces (notice te last one vboxnet0):

$ ifconfig
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
    options=3<RXCSUM,TXCSUM>
    inet6 ::1 prefixlen 128 
    inet 127.0.0.1 netmask 0xff000000 
    inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1 
    inet 172.16.0.9 netmask 0xffff0000 
    nd6 options=1<PERFORMNUD>
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
    options=10b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV>
    ether 38:c9:86:4f:bd:74 
    inet6 fe80::3ac9:86ff:fe4f:bd74%en0 prefixlen 64 scopeid 0x4 
    inet 10.0.0.2 netmask 0xffff0000 broadcast 10.0.255.255
    nd6 options=1<PERFORMNUD>
    media: autoselect (1000baseT <full-duplex,flow-control,energy-efficient-ethernet>)
    status: active
en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
    ether 08:6d:41:e9:79:7e 
    inet6 fe80::a6d:41ff:fee9:797e%en1 prefixlen 64 scopeid 0x5 
    inet 10.0.1.2 netmask 0xffff0000 broadcast 10.0.255.255
    nd6 options=1<PERFORMNUD>
    media: autoselect
    status: active
en2: flags=963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX> mtu 1500
    options=60<TSO4,TSO6>
    ether 2a:00:01:66:53:30 
    media: autoselect <full-duplex>
    status: inactive
en3: flags=963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX> mtu 1500
    options=60<TSO4,TSO6>
    ether 2a:00:01:66:53:31 
    media: autoselect <full-duplex>
    status: inactive
p2p0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 2304
    ether 0a:6d:41:e9:79:7e 
    media: autoselect
    status: inactive
awdl0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1484
    ether 4a:00:05:4b:ef:d9 
    inet6 fe80::4800:5ff:fe4b:efd9%awdl0 prefixlen 64 scopeid 0x9 
    nd6 options=1<PERFORMNUD>
    media: autoselect
    status: active
bridge0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
    options=63<RXCSUM,TXCSUM,TSO4,TSO6>
    ether 3a:c9:86:f4:af:00 
    Configuration:
        id 0:0:0:0:0:0 priority 0 hellotime 0 fwddelay 0
        maxage 0 holdcnt 0 proto stp maxaddr 100 timeout 1200
        root id 0:0:0:0:0:0 priority 0 ifcost 0 port 0
        ipfilter disabled flags 0x2
    member: en2 flags=3<LEARNING,DISCOVER>
            ifmaxaddr 0 port 6 priority 0 path cost 0
    member: en3 flags=3<LEARNING,DISCOVER>
            ifmaxaddr 0 port 7 priority 0 path cost 0
    nd6 options=1<PERFORMNUD>
    media: <unknown type>
    status: inactive
ppp0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1280
    inet 10.0.0.2 --> 10.0.2.3 netmask 0xffff0000 
vboxnet0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
    ether 0a:00:27:00:00:00 
inet 172.16.0.1 netmask 0xfff00000 broadcast 172.31.255.255

When You do the port forwarding from loopback device to other host (virtual host) the source address of the forwarded packet isn't changed. But it has the same loopback ip address 127.0.0.1. When other host (virtual host) recives the forwarded packet it answers to its own loopback device. That is why you haven't connection.

Use other ip (not from loopback's 127.0.0.0/8 network) on your host server for port forwarding.