▁isolated ▁by ▁G iese cke , ▁but ▁the ▁formula ▁was ▁suggested ▁by ▁B ly th ▁and ▁definitely ▁established ▁by ▁Hoff mann . ▁ ▁D -( S )- Con i ine ▁has ▁since ▁been ▁determined ▁to ▁be ▁a ▁color less ▁al kal ine ▁liquid , ▁with ▁a ▁pen etr ating ▁od our ▁and ▁a ▁burning ▁taste ; ▁has ▁D 0 °   0 . 8 6 2 6 ▁and ▁D 1 9 °   0 . 8 4 3 8 , ▁ref ract ive ▁index ▁n 2 3 ° D ▁ 1 . 4 5 0 5 , ▁and ▁is ▁de xt ror ot atory , ▁[ α ] 1 9 ° D ▁+ 1 5 . 7 ° . ▁( See ▁comments ▁about ▁the ▁specific ▁rotation ▁below , ▁under ▁" En anti om ers ". ) ▁L -( R )- Con i ine ▁has ▁[ α ] 2 1 ° D ▁ 1 5 ° ▁and ▁in ▁other ▁respect s ▁res emb les ▁its ▁D - is omer , ▁but ▁the ▁sal ts ▁have ▁slightly ▁different ▁mel ting ▁points ; ▁the ▁plat in ich lor ide ▁has ▁mp . ▁ 1 6 0   ° C ▁( L öff ler ▁and ▁Friedrich ▁report ▁ 1 7 5   ° C ), ▁the ▁aur ich lor ide ▁mp . ▁ 5 9   ° C . ▁ ▁Sol ub ility ▁Con i ine ▁is ▁slightly ▁sol ub le ▁( 1 ▁in ▁ 9 0 ) ▁in ▁cold ▁water , ▁less ▁so ▁in ▁hot ▁water