We present ALMA observations of cold dust and molecular gas in four high-luminosity , heavily reddened ( A _ { V } \sim 2.5 - 6 mag ) Type 1 quasars at z \sim 2.5 with virial M _ { BH } \sim 10 ^ { 10 } M _ { \odot } , to test whether dusty , massive quasars represent the evolutionary link between submillimetre bright galaxies ( SMGs ) and unobscured quasars .
All four quasars are detected in both the dust continuum and in the ^ { 12 } CO ( 3-2 ) line .
The mean dust mass is 6 \times 10 ^ { 8 } M _ { \odot } assuming a typical high redshift quasar spectral energy distribution ( T=41K , \beta =1.95 or T=47K , \beta =1.6 ) .
The implied star formation rates are very high - \gtrsim 1000 M _ { \odot } yr ^ { -1 } in all cases .
Gas masses estimated from the CO line luminosities cover \sim 1-5 \times 10 ^ { 10 } ( \alpha _ { CO } / 0.8 ) M _ { \odot } and the gas depletion timescales are very short - \sim 5 - 20 Myr .
A range of gas-to-dust ratios is observed in the sample .
We resolve the molecular gas in one quasar - ULASJ2315 + 0143 ( z = 2.561 ) - which shows a strong velocity gradient over \sim 20 kpc .
The velocity field is consistent with a rotationally supported gas disk but other scenarios , e.g .
mergers , can not be ruled out at the current resolution of these data .
In another quasar - ULASJ1234+0907 ( z = 2.503 ) - we detected molecular line emission from two millimetre bright galaxies within 200 kpc of the quasar , suggesting that this quasar resides in a significant over-density .
The high detection rate of both cold dust and molecular gas in these sources , suggests that reddened quasars could correspond to an early phase in massive galaxy formation associated with large gas reservoirs and significant star formation .