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[交流] 有关三硫代碳酸酯RAFT试剂的制备问题

以下文章中关于RAFT试剂合成的节选，合成方法中只用到了二硫化碳，氯仿，丙酮，氢氧化钠，以及甲基三辛基氯化铵做相转移催化剂，我现在有几个疑问：
（1）反应温度一定要控制在10°c吗？
(2) 搅拌过夜是多久？十二个小时够吗？
（3）最后用异丙醇溶解布氏漏斗收集的固体物质，未溶解的固体黄色物质不是我们所要得到的目标产物吧？而异丙醇溶液旋蒸以后出现的黄色固体物质是我们的目标产物？
（4）最后那个通过正己烷提纯的问题，是直接加入正己烷以后没有溶解的物质就是我们要得到的结晶物质吗》？还是要通过加热等？楼主能告诉我详细的步骤吗？
（5）有谁能提供一张红外看看嘛？关键，谢谢

具体合成方法：
Synthesis of S-1-Dodecyl-S ′ -( R , R ′ -dimethyl- R ′′ -acetic acid)trithiocarbonate , 2. 1-Dodecanethiol (80.76 g, 0.40mol), acetone (192.4 g, 3.31 mol), and Aliquot 336(tricaprylylmethylammonium chloride, 6.49 g, 0.016 mol) were mixed in a jacketed reactor cooled to 10 °Cunder a nitrogen atmosphere. Sodium hydroxide solu-tion (50%) (33.54 g, 0.42 mol) was added over 20 min.The reaction was stirred for an additional 15 min before carbon disulfide (30.42 g, 0.40 mol) in acetone (40.36 g,0.69 mol) was added over 20 min, during which time the color turned red. Ten minutes later, chloroform (71.25 g, 0.60 mol) was added in one portion, followed by dropwise addition of 50% sodium hydroxide solution(160 g, 2 mol) over 30 min The reaction was stirred overnight. 600 mL of water was added, followed by 100mL of concentrated HCl ( caution! gas, odor) to acidify the aqueous solution. Nitrogen was purged through the reactor with vigrous stirring to help evaporate off acetone. The solid was collected with a Buchner funnel and then stirred in1Lof2-propanol. The undissolved solid was filtered off and was identified as S,S′-bis(1-dodecyl)trithiocarbonate. The 2-propanol solution was concentrated to dryness, and the resulting solid was recrystallized from hexanes to afford 92.5 g of yellow crystalline solid;

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